a trip to the (flowing!) comanche springs

IMG_6527Hunting for crawfish in the canal just downstream of the pool. The salt rim on the sides suggests a waning flow.

Comanche Springs (originally named Awache, Comanche for “wide water”) was a Comanche stop into and out of Mexico (and surely a pre-historic stop for water in a land where water iss scarce). Later, the U.S. Army established a fort at the springs, Fort Stockton, which also sparked the town that eventually assumed the same name.

The springs consistently produced about 42 cubic feet per second, equivalent to about 30,000 acre-feet per year. Starting in 1875, farmers began diverting flows for irrigation just downstream of the springs. In 1938, Pecos County built a swimming pool and pavilion at the major springs. In 1947, in response to nearby pumping from newly installed irrigation wells, springflow began to steadily decline, failing for the first time in March of 1961.

By that time, about 100 families farming about 6,000 acres relied on the springs for their livelihood, so they sued the groundwater pumpers. However, due to a Texas Supreme Court case in 1904 that established the Rule of Capture for groundwater in the state, the downspring farmers lost when the Texas Supreme Court refused to hear their case and when the legislature refused to address their concerns. Rule of Capture states that you have the right to capture groundwater beneath your land and put it to beneficial use regardless of how your pumping affects your neighbors. Legal jousting has returned in recent years as locals debate how much water should be exported to far-away, thirsty cities.

Depending on how much pumping has occurred the year before and how early the farmers start pumping for the new growing season, the Comanche Springs gurgle to life and flow once again for several weeks to a few months in the spring. Visiting the flowing springs has been on my hydrologic bucket list for many years (I’ve seen them dry many a time), so when I heard last week that they had sprung to life, I hightailed out to Fort Stockton yesterday to have a looksee.

I started at the upper springs (Blue Hole and Koehler SPrings), large seeps that were probably grand back in the day based on the concrete and stone curbs around them. The flows were not impressive, and, as a result, the concrete spring run was chocked with green slime. However, a healthy flow churned out of the pool into the canal, clearing the water with a vigorous flow.

I didn’t have a flowmeter with me (the weekend crept up quick…), but I did bring a ruler to measure depth and had my watch to estimate the surface velocity of the flow. I calculated a flow of about 5 cubic feet per second (I cheeseballed this calculation while drinking part of a Becker Vineyards allocation I picked up on the way back home, so please check my work if you feel inclined: 36-inch diameter pipe filled to 16 inches with a surface velocity for water coming out of the pipe of 2 feet per second).

I traced the springflow downstream as far as I could and also visited the farms irrigated with groundwater.

Here’s a map of the springs from the book Fort Stockton:


IMG_6457The uppermost flowing spring at Blue Hole.

IMG_6451The second most uppermost flowing spring, Koehler’s Spring.

IMG_6478Koehler’s Spring where it discharges to the canal. Not much discharge from these two springs.

Upstream of the two uppermost springs, the canal is dry (although there was a wet spot in part of the canal (not shown).

IMG_6445Approaching the major springs at the pool. The water in the canal here is primarily backflow caused by a large discharge from the major springs.

IMG_6530Sadly, despite 90-degree temps, the pool was not open, so I took this shot peering over the fence. The caged shed center left houses Big Chief Spring, which I could hear violently gurgling away at this distance. Government Spring, on the other side of the pool to the right, held no water nor emitted a sound. The swimming pool you see is a shell sitting atop an open vault on the sides and bottom to allow spring flow to flow out without damaging the pool. The county built the shell after the springs dried up in the 1950s. 

A close-up of the caged Big Chief Spring, a photo I took a year ago November.

IMG_0701_tonemappedGovernment Spring from a year ago November.

This pipe is where flow out of the pool springs discharges into the canal.

A number of folks were in the canal looking for crawdads. A family showed me their catch, some of which were 8 inches long.

IMG_6505This is just downstream of Highway 285 where an old diversion dam directs flow into the old irrigation channel to the left and overflows to the right.

IMG_6508This is the downstream side of the diversion channel, the concrete support fins slowly crumbling away.

IMG_6514Someone has dug around the side of the overflow structure to prevent the water from backing up too much.

I tracked how far the flow was making it down the canal:

IMG_6563This is the flow downstream of Highway 385. Right before I pressed “click”, several ducks enjoying the canal disembarked.

IMG_6575This is the flow on the upstream side of the Interstate 10 frontage road, where the water dumped into a vault that runs underneath the highway in two directions.

IMG_6590The flow emerges on the other side of Interstate 10 and appears to simply be discharged into Comanche Creek.

IMG_6593Panning to the right. If you look closely on the right, you can see water pooling.

I wandered down the canals a little more to verify nothing was going any farther, and found them dry and abandoned:

IMG_6566The “eastern” canal at 7 D Road looking downstream.

IMG_6581The “western” canal (called the Highline Ditch in Google Maps) at Stone Road looking downstream.

IMG_6584An abandoned standpipe off the “western” canal near Stone Road.

The “western” canal (called the Highline Ditch in Google Maps) at Stone Road looking upstream. You have to look closely (follow the pear…) to see the “canal”.

I also drove out to where the pumps run from the aquifer:

IMG_6548New pecan trees going in west of town.

It’s surprising, at least to me, how far out of town the groundwater pumping is, about five to six miles. I doubt anyone knew at the time that pumping out here would dry up the springs in Fort Stockton.

Screen Shot 2018-03-11 at 5.12.22 PMFollow the green… The dark-green elongated spot on the east side of Fort Stockton is Comanche Springs; all the green on the left side of the image are the irrigated farms whose pumping dried up the springs.

And now for some historical shots!

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The springs used to be called Government Springs. This is probably from around 1910.

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Fort Stockton 08
This is a pre-pavilion aerial of the springs showing the natural bottom of the pool. On the far side is the old changing rooms.

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A different view.

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A close-up of the old changing rooms and one of the springs (caged even back then).

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Here’s a postcard showing the new pavilion with the old changing rooms demolished. You can also see Big Chief Spring. Note how the stairs on the left descend to the water.

IMG_6536Here’s a photo I took yesterday where you can still see the stairs, but now they descend to a deck. Below that deck is a cavity to allow the episodic spring flow to escape and to have a non-springfed swimming pool.

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The arrow points at Big Chief Spring. Towards the center-bottom is a stage being built (or torn down) for Fort Stockton’s annual Water Carnival.


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du ponts’ artesian well in louisville, kentucky (1858)

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After Mulot imported Chinese cable-tool drilling to the western world and successfully sank a flowing artesian well in Paris, water wildcatters worldwide slowly began chipping into the depths in search of artesian water. The du Ponts drilled one such well in Louisville, Kentucky; a well nicely described by Professor J. Lawrence Smith of the University of Louisville (Smith 1859).

Some tidbits on the well from Smith’s report:

  • The well was located at the Louisville Paper Mill on Tenth Street near Main.
  • The well was drilled by C.I. and A.V. du Pont.
  • A Mr. Bake drilled the well.
  • The well hit an artesian flow of mineral water in August of 1858 at a depth of 2,086 feet,
  • An excerpt from Tomlinson’s Encyclopedia states that artesian wells in France had been used to power a flour mill, for irrigation, for silk spinning, to run machinery, to provide heat for greenhouses, fish ponds, a source of clear water for paper mills. Water from the Grenelle Well in Paris had been used to heat a nearby hospital and other public buildings.
  • Right before the Grenelle Well came in, the rod “suddenly descended several yards”.
  • Key wells noted by Smith:
    • the Grenelle Well,
    • the Kissingen Well in Bavaria,
    • at the monastery of St. Andre in the Aire in Artois (bored more than a century ago, water rises to 11 feet above the ground, flows 250 gallons per minute),
    • Charleston Wel in Charleston, South Carolina (1,250 feet deep, 30,000 gallons in 24 hours, flows 10 feet above the surface),
    • Belcher’s Well in St. Louis (drilled 1953-4, 108,000 gallons in 24 hours, 2,199 feet deep),
    • Lafayette Well in Lafayette, Indiana (230 feet deep, mineral water, 4 gallons per minute)
  • Dupont’s well: 330,000 gallons per 24 hours, the elevation of water above the surface was 170 feet.
  • Drilling started in April 1857.
  • Three-inch borehole.
  • Cased to 76 feet deep.
  • Water temperature was 76.5 degrees F at the wellhead, bottom-hole temp was 82.5.
  • “…it will doubtless flow in undiminished quantity for centuries to come; as wells having such deep sources as this are usually inexhaustible.”
  • “The solid contents left on evaporating one wine gallon to dryness are 915.5 grains….” [I hadn’t heard of a wine gallon before (appears to be equal to an American gallon)! One grain per gallon equals 17.1 parts per million, so 915.5 grains per gallon is 15,655 parts per million. About two-thirds of the grains are chlorides.]
  • Smith on the medicinal properties of mineral waters: “If taken moderately they excite the appetite, and are looked upon as a mid and efficacious aid to digestion; in still larger doses they excite in a more marked manner the entire mucous lining of the intestinal canal, extending to the liver; and, taken into the circulation, their effects are felt in al secretive and excretive organs, as the kidneys, etc.”

Smith (1859 p4) includes a nice description of drilling an artesian well:

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According to Kleber (2015), the well was drilled by Charles I. and Alfred Victor du Pont seeking a source of “pure and soft water” for papermaking. Tobaco Realty Co. sealed the top of the well in 1923 and diverted its flow to the sewer. The well was plugged in 1948.


Kleber, J.E., 2015, Lousiville Artesian Well in The Encyclopedia of Louisville: University Press of Kentucky, 1,024 p.

Smith, J.L., 1859, DuPont’s artesian well, Louisville, Kentucky–Report, analysis, and medical properties of its water, with remarks upon the nature of artesian wells: The Medical Department of the University of Louisville, Kentucky, 22 p. [source]


Water! Plenty of It: Enough for one thousand homes

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Neat advertisement for a development in East Dallas spouting off (so to speak…) about its flowing artesian well. Vickery Place as a development began in 1911; this enticement was published in the Dallas Morning News on June 11, 1911.

According to “The Geology of Dallas County” by Ellis Shuler, the Vickery Place well intercepted sands at 503 to 526 feet, 626 to 627 feet, and 666 to 700 feet below the base of the Austin Chalk, indicating that the well was completed in the Woodbine Aquifer, a minor aquifer above the Trinity Aquifer.

Thanks to Paula Ross and FLASHBACK : DALLAS for the tip and image!

Wikipedia entry on Vickery Place

Shuler, E., 1918, The Geology of Dallas County: University of Texas Bulletin, no. 1818, 54 p.

Side note:

Shuler’s report includes a photograph of a flowing artesian well drilled in 1914 at Southern Methodist Univerisity:

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yapping about artesian wells (and water conservation) in Austin


I’ll be yipping and yapping about the history of artesian wells on February 1st (8a to 3:30p at the Canyon View Event Center in Austin) at the Central Texas Water Conservation Symposium. The title of the symposium is “Future-Focused Water Conservation–Past to Present: What’s Next on the Horizon?” My presentation is past-focused with the historical tidbit that legislative action that came out of the uncontrolled flow of artesian water was the first (real) nod toward water conservation in Texas. The agenda has a great line-up of speakers concerning water conservation (and looking forward!). Speaking of looking forward, I look forward to seeing you there!

Here’s how to register.




details subject to change

Oldie but Goodie: Underground waters of the Rio Grande Plain and Edwards Plateau (Hill and Vaughan 1898)

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“Geology of the Edwards Plateau and Rio Grande Plain Adjacent to Austin and San Antonio, Texas, with Reference to the Occurrence of Underground Waters” by Robert T. Hill and T. Wayland Vaughan published by the U.S. Geological Survey in 1898 (works volume 4, annual report volume 18, part 2, pages 199-321 with plates) captures the early years of artesian well wildcatting in the Austin to San Antonio to Del Rio area. The report also has some fabulous early photographs of key springs and flowing artesian wells in the area. Hill and Vaughan include quite a bit about the area’s geology (didja know that the Edwards used to be referred to as the Caprina limestone?), but I’ll focus on the hydrogeological bits here.

Of great interest to the authors, especially as they might relate to underground waters, were the springs along the edge of the plateau:

At intervals along- the interior boundary of the Rio Grande Plain from Austin to Devils River, through a distance of 300 miles, there is a series of remarkable springs which rise out of the ground. They do not break out from bluffs or fall in cascades, but appear as extensive pools, often in the level prairie. These pools or small lakes of limpid blue water find their outlet in swift and silently flowing streams.

The pools are carpeted with rare water plants, among which many fishes may be seen swimming. So transparent are these waters that objects 15 to 20 feet below the surface appear to be only a few feet away. They have been filtered by passing through the pores of the rocks for many miles.

The most conspicuous of these springs are near Del Rio, Brackett, San Antonio, New Braunfels, San Marcos, Manchaca, and Austin. In addition to these there are large springs north of the Colorado at Round Rock, Georgetown, Salado, Belton, and other places, as well as numerous small springs which need not be mentioned. The Cedar springs, north of Dallas, are probably the most northern of the line.

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Hill and Vaughan discuss the half dozen artesian wells drilled in the Austin area, including wells sunk at the capitol, the Insane Asylum, St. Edwards, and the Austin Natatorium:

The Asylum well had a discharge of 150,000 gallons a day and threw the water to a height of 40 feet. The Asylum well is 1,975 feet deep. In the Asylum well the above-mentioned flow is separated by about 160 feet of limestone and shale from the third and lowest of the waterbearing beds, the basement, Travis Peak, or “Trinity” sands. These produce the purest water, and ordinarily the most, of all the waterbearing strata of the series. It will be seen that only one of the wells has positively penetrated the entire series of beds composing the Cretaceous system, thereby exploiting its fullest capacity and reaching into the underlying impervious Paleozoic formations. This is the well at the Insane Asylum.

The St. Edward’s well, sunk in the winter of 1892-93, is 2,053 feet deep

In St Edward’s well … the water comes within about5 feet of the surface and has to be pumped.

Two artesian wells have been bored by the State authorities on the capitol grounds. The first of these was in the year 1858 and was carried to a depth of only 471 feet.

Log of the Austin Natatorium artesian well, drilled by Hugh McGillivray, at the corner of San Jacinto and Fifth streets, Austin, Texas. The flow is about 250,000 gallons a day, and is increasing; temperature, 100°.

A valuable contribution to the extent of the artesian field in Travis County was made by the drilling of the well at Manor, in 1895. Quantity of water discharged per hour, 4,166 gallons. Size of discharge pipe, 6 inches. Temperature of water, 93°.  Water will rise in pipe about 30 feet above the surface. The first effort to dig this well failed, as it caved in at the depth of about 1,100 feet. The present well, bored by Mr.  J. Eppright, was finished about February 13, 1896, and cost $4,000.

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“[We] have referred all the wells to a common geologic datum—the top of the Shoal Creek limestone…” The Shoal Creek limestone is now known as the Buda limestone.

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Many of the wells drilled in the Austin area at this time were not fresh. For example, the Natatorium well sunk at San Jacinto and Fifth had total dissolved solids north of 10,000 parts per million (see table immediately above).

Down in San Marcos there was, of course, San Marcos Springs, but also the recently drilled well for the fish hatchery, a well that made the national papers after producing blind critters from the depths (including Satan!).


At the village of San Marcos a great group of springs breaks out at the foot of a north-south line of bluffs making the Balcones scarp line in this region, and form the source of a beautiful river flowing 57,000,000 gallons per day. This has long been a famous resort in Texas on account of the exquisite aqueous flora and the beauty of the water. The springs form a lake nearly half a mile long, and its runoff forms the San Marcos River. At the lower end of the lake a mill and an ice factory are run by its water, and the United States Fish Commission has established a culture station here. While none of the water is utilized in irrigation, there is no reason why such a volume of water should not be used to irrigate considerable areas of the fertile Black Prairie lands.

Two records of an artesian well drilled for the United States Fish Commission at San Marcos in the year 1895 afford the most complete well section we have been able to obtain in the Rio Grande Plain. The well was drilled to a depth of 1,490 feet, and when stopped was still in the Cretaceous formations, about 175 feet above the estimated base of the Asylum well, at Austin.

There are one or two elements of perplexity concerning the San Marcos well which also present themselves at San Antonio. It is located almost upon the line of a great fault, which may be seen on the west side of the spring pool a short distance from the well. It is possible that the drill hole may cross this fault line not far below the surface, and that the so-called caverns are its waterworn fissures. The fact that this water was full of peculiar cave-inhabiting animals indicates that there are cavities beneath the ground, the extent of which, however, can not be stated. These maybe pockets, such as are seen in the outcrops of the Edwards limestone, or they maybe extensive caves, like the Hillcoat caverns of Edwards County. The fact that the drill passed through only 2 feet of cavity rather opposes the latter hypothesis.

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For New Braunfels, Hill and Vaughan quoted Dr. Evermann:

There are a great many springs in the vicinity of New Braunfels, the principal group being known as the Coma] springs. There are several springs in this group situated upon the land of Mr. Joseph Landa, a little over a mile northwest of New Braunfels. The largest of these flows, perhaps, as much as 50,000 gallons per minute, and is certainly a magnificent spring. The other springs of the same group flow at least as much more.”

The main spring comes out near the foot of a limestone hill, and after running rapidly for a short distance over a pebbly bottom and in a narrow channel, it widens out into quite a pond with mud bottom and filled with vegetation. This pond also receives the water from numerous other springs, and has its outlet in Comal Creek (or the Rio Comal), which, after a course of2 or 3 miles, joins the Guadalupe River. The water of these springs is, of course, very clear. The temperature is 75°.

Hill and Vaughan identified 40 artesian wells in the San Antonio area and, interestingly, noted the gradual failure of San Pedro and San Antonio springs due to artesian well production. The wells included those drilled by Colonel C.M. Terrell, the Menger Hotel, the Santa Rosa Hospital, the city, and the Crystal Ice Company.

Many of the large springs, and some of the most noted of their class, occur in the vicinity of San Antonio, the largest being at the head of the San Antonio River, a few miles north of the city. Until recently these flowed out of the ground in great volume—27,000,000 gallons per day—forming an exquisite lake, the run-off of which is the San Antonio River, which flows through the heart of the city of San Antonio and supplies it with water.

Below this group of springs and upon the banks of its outflow was situated one of the most ancient Indian settlements, or pueblos, of Texas. The early Spanish priests, appreciating the beauties and natural advantages of the place, located several missions there within a short distance of one another. The natives were employed in the cultivation of farms and gardens irrigated by the spring waters. The ancient acequias or ditches, followed by the older streets, shape the present outline of the city.

The spring-fed river furnished, until recently, water for the city of 48,000 inhabitants without very appreciably diminishing its volume. Many acres of gardens and farms were irrigated, and there was sufficient water to irrigate many more. As elsewhere shown, the flow of the river has been recently seriously diminished by the drilling of numerous wells around San Antonio.

The San Pedro springs are about 2 miles southwest of those above mentioned, at the head of the river. Besides supplying an irrigation ditch they constitute the nucleus of handsome pleasure grounds. The springs here break out of fissures in the Gryphoea aucella beds of the Austin chalk. Their flow is estimated at 9 second-feet, or 6,000,000 gallons per day.

A large number of wells have been drilled in and around the city of San Antonio. They occur in nearly all parts of the city and its adjacent suburbs…





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“[We] have referred all the wells to a common geologic datum—the top of the Shoal Creek limestone…” The Shoal Creek limestone is now known as the Buda limestone.

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units in parts per million

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IRISYDHT: The Fourth National Climate Assessment Report

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(IRISYDHT = I Read It So You Don’t Have To)

Human-forced climate change is a delicate topic in many policymaking circles in Texas. I half-jokingly refer to the state of the discussion in the state as an unspoken “Don’t-Ask-Don’t-Tell” policy.” Some folks clearly adhere to the science, some folks clearly don’t, and others have a “wide stance” to navigate the politics.

Regardless of your stance, it’s important to know what the climate scientists—not the policy advocates, not the scientist advocates—are finding on the climate situation. Note that I said “climate scientists.” It’s critical to listen to the specialists in the field, not some non-specialist yahoo that prattles on and on about what is or isn’t happening. It’s also important to listen to scientists (or, even better, a group of scientists) who do not advocate for policy change: in other words, scientists acting like scientists.

Furthermore, it’s key to listen to someone who qualifies their conclusions. I like to say that the best way to detect when a scientist is lying is when they say they are 100 percent positive about something. As my Ph.D. advisor liked to say: “You can never prove a hypothesis; you can only disprove it.” Science, especially climate science, is uncertain. This is not a knock on science—it’s simply the reality of studying the real world.

This fall, the U.S. Global Change Research Program released its Fourth National Climate Assessment Report. The report–put together by a group of scientists–summarizes climate science with a focus on the United States. I read the report (and write about it here) because climate change almost certainly impacts water resource in Texas. Are we seeing climate change in Texas? What might the future hold for Texas? How certain is that science?

The report is well written (although whoever acronymized Tropical Cyclone into TC needs to be kicked in the shins). It’s also well referenced, and it appropriately qualifies (assigns certainty to) each of its conclusions. The report also does a great job of explaining the scientific support–rigourous or not–for each conclusion.

Selfishly, I wish the report would have shown potential impacts to run-off, which is really where the grease hits the griddle on water supplies for both groundwater and surface water in Texas. I also wish they would employ a geographer so they wouldn’t include unprojected maps in the report (a freshman mistake and a major pet peeve of mine).

Below, I’ve pulled out the bits that I found interesting. The bits are, for the most part, verbatim, so you can search on snippets to find them in context in the report to read more. Be forewarned: There are a lot of bits here that I culled from this 470-page report. In a hopeless attempt to increase readibility, I’ve broken the bullets into groups of five.

Stay tuned for subsequent posts where I plan to discuss what the report means for water in Texas.

  • “Global annually averaged surface air temperature has increased by about 1.8°F (1.0°C) over the last 115 years (1901–2016).”
  • “…extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century…”
  • “…global average sea level has risen by about 7–8 inches since 1900, with almost half (about 3 inches) of that rise occurring since 1993…”
  • “Global average sea levels are expected to continue to rise—by at least several inches in the next 15 years and by 1–4 feet by 2100…”
  • “Heavy rainfall is increasing in intensity and frequency across the United States and globally and is expected to continue to increase.”


  • “…over the next few decades (2021–2050), annual average temperatures are expected to rise by about 2.5°F for the United States, relative to the recent past (average from 1976–2005)…”
  • “…chronic, long-duration hydrological drought is increasingly possible before the end of this century…”
  • “…the cost of extreme events for the United States has exceeded $1.1 trillion…”
  • “Sixteen of the warmest years on record for the globe occurred in the last 17 years…”
  • “Human activities are the primary driver of recent global temperature rise”


  • “Without major reductions in these emissions, the increase in annual average global temperatures relative to preindustrial times could reach 9°F (5°C) or more by the end of this century…”
  • “If greenhouse gas concentrations were stabilized at their current level, existing concentrations would commit the world to at least an additional 1.1°F…”
  • “Annual average temperature over the contiguous United States is projected to rise (very high confidence). Increases of about 2.5°F (1.4°C) are projected for the period 2021–2050 relative to the average from 1976–2005 in all RCP scenarios, implying recent record-setting years may be “common” in the next few decades (high confidence). Much larger rises are projected by late century (2071-2100): 2.8°–7.3°F (1.6°–4.1°C) in a lower scenario (RCP4.5) and 5.8°–11.9°F (3.2°–6.6°C) in a higher scenario (RCP8.5) (high confidence)…”
  • “The urban heat island effect will strengthen in the future as the structure and spatial extent as well as population density of urban areas change and grow (high confidence).”
  • “Some storm types such as hurricanes, tornadoes, and winter storms are also exhibiting changes that have been linked to climate change, although the current state of the science does not yet permit detailed understanding.”


  • “Record warm daily temperatures are occurring more often”
  • “…by geographical scale and duration, the Dust Bowl era of the 1930s remains the benchmark drought and extreme heat event in the historical record…”
  • “Northern Hemisphere spring snow cover extent, North America maximum snow depth, snow water equivalent in the western United States, and extreme snowfall years in the southern and western United States have all declined, while extreme snowfall years in parts of the northern United States have increased.”
  • “Winter storm tracks have shifted northward since 1950 over the Northern Hemisphere (medium confidence)…”
  • “The frequency and intensity of extreme high temperature events are virtually certain to increase in the future as global temperature increases (high confidence).”


  • “Extreme precipitation events will very likely continue to increase in frequency and intensity throughout most of the world (high confidence).”
  • “Cold waves are predicted to become less intense while heat waves will become more intense. The number of days below freezing is projected to decline while the number above 90°F will rise. (Very high confidence)”
  • “The frequency and intensity of heavy precipitation events in the United States are projected to continue to increase over the 21st century (high confidence).”
  • “…parts of the southwestern United States are projected to receive less precipitation in the winter and spring (medium confidence)…”
  • “Projections indicate large declines in snowpack in the western United States and shifts to more precipitation falling as rain than snow in the cold season in many parts of the central and eastern United States (high confidence).”


  • “Substantial reductions in western U.S. winter and spring snowpack are projected as the climate warms. Earlier spring melt and reduced snow water equivalent have been formally attributed to human-induced warming (high confidence) and will very likely be exacerbated as the climate continues to warm (very high confidence). Under higher scenarios, and assuming no change to current water resources management, chronic, long-duration hydrological drought is increasingly possible by the end of this century (very high confidence)”
  • “Future decreases in surface soil moisture from human activities over most of the United States are likely as the climate warms under the higher scenarios. (Medium confidence)”
  • “The human effect on recent major U.S. droughts is complicated. Little evidence is found for a human influence on observed precipitation deficits, but much evidence is found for a human influence on surface soil moisture deficits due to increased evapotranspiration caused by higher temperatures. (High confidence)”
  • “The incidence of large forest fires in the western United States and Alaska has increased since the early 1980s (high confidence) and is projected to further increase in those regions as the climate warms, with profound changes to certain ecosystems (medium confidence)”
  • “Both physics and numerical modeling simulations generally indicate an increase in tropical cyclone intensity in a warmer world, and the models generally show an increase in the number of very intense tropical cyclones. For Atlantic and eastern North Pacific hurricanes and western North Pacific typhoons, increases are projected in precipitation rates (high confidence) and intensity (medium confidence). The frequency of the most intense of these storms is pro-jected to increase in the Atlantic and western North Pacific (low confidence) and in the eastern North Pacific (medium confidence)”


  • “The Arctic is warming at a rate approximately twice as fast as the global average…”
  • “Septembers will be nearly ice-free in the Arctic Ocean sometime between now and the 2040s…”
  • “…the influence of arctic changes on U.S. weather over the coming decades remains an open question with the potential for significant impact.”
  • “The world’s oceans have absorbed about 93% of the excess heat caused by greenhouse gas warming since the mid-20th century, making them warmer and altering global and regional climate feedbacks.”
  • “Global mean sea level (GMSL) has risen by about 7–8 inches (about 16–21 cm) since 1900, with about 3 of those inches (about 7 cm) occurring since 1993 (very high confidence).”


  • “The potential slowing of the Atlantic meridional overturning circulation (AMOC; of which the Gulf Stream is one component)—as a result of increasing ocean heat content and fresh-water-driven buoyancy changes—could have dramatic climate feedbacks as the ocean absorbs less heat and CO2 from the atmosphere.”
  • “The world’s oceans are currently absorbing more than a quarter of the CO2 emitted to the atmosphere annually from human activities, making them more acidic (very high confidence)”
  • “The observed increase in global carbon emissions over the past 15–20 years has been consistent with higher scenarios (e.g., RCP8.5)…”
  • “Global mean atmospheric carbon dioxide (CO2) concentration has now passed 400 ppm, a level that last occurred about 3 million years ago…”
  • “Warming and associated climate effects from CO2 emissions persist for decades to millennia.”


  • “In recent decades, land-use and land-cover changes have turned the terrestrial biosphere (soil and plants) into a net “sink” for carbon (drawing down carbon from the atmosphere), and this sink has steadily increased since 1980 (high confidence).”
  • “There is significant potential for humanity’s effect on the planet to result in unanticipated surprises and a broad consensus that the further and faster the Earth system is pushed towards warming, the greater the risk of such surprises.”
  • “…it is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century.”
  • “Climate, on the other hand, is the statistics of weather…”
  • “…a warmer atmosphere can hold more water vapor…”


  • “…the El Niño/La Niña cycle may itself be affected by the human influence on Earth’s climate system.”
  • “Annual averaged precipitation across global land areas exhibits a slight rise (that is not statistically significant because of a lack of data coverage early in the record) over the past century…”
  • “Global atmospheric water vapor should increase by about 6%–7% per °C of warming based on the Clausius–Clapeyron relationship…”
  • “…precipitation increases of approximately 0.55% to 0.72% per °F…”
  • “Earlier studies suggested a climate change pattern of wet areas getting wetter and dry areas getting drier…”


  • “While this high/low rainfall behavior appears to be valid over ocean areas, changes over land are more complicated. The wet versus dry pattern in observed precipitation has only been attributed for the zonal mean…”
  • “The detected signal in zonal mean precipitation is largest in the Northern Hemisphere, with decreases in the subtropics and increases at high latitudes.”
  • “…the science of event attribution is rapidly advancing…”
  • “On a global scale, the observational annual-maximum daily precipitation has increased by 8.5% over the last 110 years…”
  • “Extreme precipitation events are increasing in frequency globally over both wet and dry regions…”


  • “…extreme precipitation associated with tropical cyclones (TCs) is expected to increase in the future,87 but current trends are not clear…”
  • “…there is low confidence for any significant current trends in river-flooding as-sociated with climate change…”
  • “…but the magnitude and intensity of river flooding is projected to increase in the future.”
  • “…there is evidence for a global increase in severe thunderstorm conditions.”
  • “Winter storm tracks have shifted slightly northward (by about 0.4 degrees latitude) in recent decades over the Northern Hemisphere.”


  • “…the locations where tropical cyclones reach their peak intensity have migrated poleward in both the Northern and Southern Hemispheres, in concert with the independently measured expansion of the tropics…”
  • “Tropical cyclone intensities are expected to increase with warming, both on average and at the high end of the scale, as the range of achievable intensities expands, so that the most intense storms will exceed the intensity of any in the historical record…”
  • “Global land-use change is estimated to have released 190 ± 65 GtC (gigatonnes of carbon) through 2015…”
  • “Over the same period, cumulative fossil fuel and industrial emissions are estimated to have been 410 ± 20 GtC, yielding total anthropogenic emissions of 600 ± 70 GtC, of which cumulative land-use change emissions were about 32%…”
  • “…a lengthening growing season, primarily due to the changing climate, and elevated CO2 is expected to further lengthen the growing season in places where the length is water limited…”


  • “…global annual averaged temperatures for 1986–2015 are likely much higher, and appear to have risen at a more rapid rate during the last 3 decades, than any similar period possibly over the past 2,000 years or longer…”
  • “…studies of past climates suggest that such global temperatures were likely last observed during the Eemian period—the last interglacial—125,000 years ago; at that time, global temperatures were, at their peak, about 1.8°F–3.6°F (1°C–2°C) warmer than preindustrial temperatures.”
  • “Coincident with these higher temperatures, sea levels during that period were about 16–30 feet (6–9 meters) higher than modern levels…”
  • “Even at equilibrium, internal variability in Earth’s climate system causes limited annual- to decadal-scale variations in regional temperatures and other climate parameters that do not contribute to long-term trends.”
  • Carbonation of finished cement products is a sink of atmospheric CO2…”


  • “…offsetting a substantial fraction (0.43) of the industrial-era emissions from cement production…”
  • “Methane is a stronger GHG than CO2 for the same emission mass and has a shorter atmospheric lifetime of about 12 years.”
  • “Contrails and contrail cirrus are additional forms of cirrus cloudiness that interact with solar and thermal radiation to provide a global net positive RF and thus are visible evidence of an anthropogenic contribution to climate change.”
  • “…an increase in low clouds is a negative feedback to RF, while an increase in high clouds is a positive feedback. The potential magnitude of cloud feedbacks is large compared with global RF…”
  • “Cloud feedbacks also influence natural variability within the climate system and may amplify atmospheric circulation patterns and the El Niño–Southern Oscillation.”


  • “Basic principles of carbon cycle dynamics in terrestrial ecosystems suggest that increased atmospheric CO2 concentrations can directly enhance plant growth rates and, therefore, increase carbon uptake…”
  • “Detection and attribution at regional scales is generally more challenging than at the global scale for a number of reasons. At the regional scale, the magnitude of natural variability swings are typically larger than for global means…”
  • “When an extreme weather event occurs, the question is often asked: was this event caused by climate change? A generally more appropriate framing for the question is whether climate change has altered the odds of occurrence of an extreme event like the one just experienced.”
  • “To our knowledge, no extreme weather event observed to date has been found to have zero probability of occurrence in a preindustrial climate, according to climate model simulations.”
  • “Hoerling et al. concluded that the 2011 Texas heat wave/meteorological drought was primarily caused by antecedent and concurrent negative rainfall anomalies due mainly to natural variability and the La Niña conditions at the time of the event, but with a relatively small (not detected) warming contribution from anthropogenic forcing.”


  • “The anthropogenic contribution nonetheless doubled the chances of reaching a new temperature record in 2011 compared to the 1981–2010 reference period…”
  • “Rupp et al., meanwhile, concluded that extreme heat events in Texas were about 20 times more likely for 2008 La Niña conditions than similar conditions during the 1960s.”
  • “In the illustrative case for the 2011 Texas heat/drought, we conclude that there is medium confidence that anthropogenic forcing contributed to the heat wave, both in terms of a small contribution to the anomaly magnitude and a significant increase in the probability of occurrence of the event.”
  • “If greenhouse gas concentrations were stabilized at their current level, existing concentrations would commit the world to at least an additional 1.1°F (0.6°C) of warming over this century relative to the last few decades (high confidence in continued warming, medium confidence in amount of warming).”
  • “Over the next two decades, global temperature increase is projected to be between 0.5°F and 1.3°F (0.3°–0.7°C) (medium confidence)”


  • “Even if existing concentrations could be immediately stabilized, temperature would continue to increase by an estimated 1.1°F (0.6°C) over this century, relative to 1980–1999.”
  • “The resulting range reflects the uncertainty inherent in quantifying human activities (including technological change) and their influence on climate.”
  • “The tropics have expanded poleward by about 70 to 200 miles in each hemisphere over the period 1979–2009, with an accompanying shift of the subtropical dry zones, midlatitude jets, and storm tracks (medium to high confidence). Human activities have played a role in this change (medium confidence), although confidence is presently low regarding the magnitude of the human contribution relative to natural variability.”
  • “Recurring patterns of variability in large-scale atmospheric circulation (such as the North Atlantic Oscillation and Northern Annular Mode) and the atmosphere–ocean system (such as El Niño–South-ern Oscillation) cause year-to-year variations in U.S. temperatures and precipitation (high confidence). Changes in the occurrence of these patterns or their properties have contributed to recent U.S. temperature and precipitation trends (medium confidence), although confidence is low regarding the size of the role of human activities in these changes.”
  • “The tropics have expanded poleward by about 70 to 200 miles in each hemisphere over the period 1979–2009, with an accompanying shift of the subtropical dry zones, midlatitude jets, and storm tracks (medium to high confidence).”


  • “Changes in the occurrence of these patterns or their properties have contributed to recent U.S. temperature and precipitation trends (medium confidence), although confidence is low regarding the size of the role of human activities in these changes.”
  • “The tropics have expanded poleward by about 70 to 200 miles in each hemisphere over the period 1979–2009, with an accompanying shift of the subtropical dry zones, midlatitude jets, and storm tracks (medium to high confidence). Human activities have played a role in this change (medium confidence), although confidence is presently low regarding the magnitude of the human contribution relative to natural variability.”
  • “Recurring patterns of variability in large-scale atmospheric circulation (such as the North Atlantic Oscillation and Northern Annular Mode) and the atmosphere–ocean system (such as El Niño–South-ern Oscillation) cause year-to-year variations in U.S. temperatures and precipitation (high confidence). Changes in the occurrence of these patterns or their properties have contributed to recent U.S. temperature and precipitation trends (medium confidence), although confidence is low regarding the size of the role of human activities in these changes.”
  • “On an interannual time scale, coupled atmosphere–ocean phenomena like El Niño–Southern Oscillation (ENSO) have a prominent effect. On longer time scales, U.S. climate anomalies are linked to slow variations of sea surface temperature related to the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO).”
  • “…there are still large uncertainties in our understanding of the impact of human-induced climate change on atmospheric circulation…”


  • “…the confidence in any specific projected change in ENSO variability in the 21st century remains low.”
  • “Evidence continues to mount for an expansion of the tropics over the past several decades, with a poleward expansion of the Hadley cell and an associated poleward shift of the sub-tropical dry zones and storm tracks in each hemisphere.”
  • “Recent estimates of the widening of the global tropics for the period 1979–2009 range between 1° and 3° latitude (between about 70 and 200 miles) in each hemisphere, an average trend of between approximately 0.5° and 1.0° per decade.”
  • “Due to human-induced greenhouse gas increases, the Hadley cell is likely to widen in the future, with an accompanying poleward shift in the subtropical dry zones, midlatitude jets, and storm tracks.”
  • “Large uncertainties remain in projected changes in non-zonal to regional circulation components and related changes in precipitation patterns.”


  • “Uncertainties in projected changes in midlatitude jets are also related to the projected rate of arctic amplification and variations in the stratospheric polar vortex. Both factors could shift the midlatitude jet equatorward, especially in the North Atlantic region.”
  • “A cooling trend of the tropical Pacific Ocean that resembles La Niña conditions contributed to drying in southwestern North America from 1979 to 2006 and is found to explain most of the decrease in heavy daily precipitation events in the southern United States from 1979 to 2013.”
  • “It is not clear whether observed decadal-scale modulations of ENSO properties, including an increase in ENSO amplitude and an increase in frequency of CP El Niño events are due to internal variability or anthropogenic forcing.”
  • “Climate projections suggest that ENSO will remain a primary mode of natural climate variability in the 21st century…”
  • “Climate models do not agree, however, on projected changes in the intensity or spatial pattern of ENSO.”


  • “Model studies suggest an eastward shift of ENSO-induced teleconnection patterns due to greenhouse gas-induced climate change.69, 70, 71, 72 However, the impact of such a shift on ENSO-induced climate anomalies in the United States is not well understood.”
  • “…there is high confidence that, in the 21st century, ENSO will remain a main source of climate variability over the United States on seasonal to interannual timescales.”
  • “There is low confidence for a specific projected change in ENSO variability.”
  • “A negative NAO phase is related to anomalously cold conditions and an enhanced number of cold outbreaks in the eastern United States, while a strong positive phase of the NAO tends to be associated with above-normal temperatures in this region.”
  • “The PDO does not show a long-term trend…”


  • “…there is low confidence in projected future changes in the PDO/IPO…”
  • “The North Atlantic Ocean region exhibits coherent multidecadal variability that exerts measurable impacts on regional climate for variables such as U.S. precipitation and Atlantic hurricane activity…”
  • “The internal part of the observed AMV is often referred to as the Atlantic Multidecadal Oscillation (AMO) and is putatively driven by changes in the strength of the Atlantic Meridional Overturning Circulation (AMOC).”
  • “…it is unclear what the statistically derived AMO indices represent, and it is not readily supportable to treat AMO index variability as tacitly representing natural variability…”
  • “Annual average temperature over the contiguous United States has increased by 1.2°F (0.7°C) for the period 1986–2016 relative to 1901–1960 and by 1.8°F (1.0°C) based on a linear regression for the period 1895–2016 (very high confidence). Surface and satellite data are consistent in their depiction of rapid warming since 1979 (high confidence)”


  • “Paleo-temperature evidence shows that recent decades are the warmest of the past 1,500 years (medium confidence)”
  • “The frequency of cold waves has decreased since the early 1900s, and the frequency of heat waves has increased since the mid-1960s.”
  • “The Dust Bowl era of the 1930s remains the peak period for extreme heat.”
  • “Annual average temperature over the contiguous United States is projected to rise (very high confidence).”
  • “Increases of about 2.5°F (1.4°C) are projected for the period 2021–2050 relative to 1976–2005 in all RCP scenarios, implying recent record-setting years may be “common” in the next few decades (high confidence).”


  • “Much larger rises are projected by late century (2071-2100): 2.8°–7.3°F (1.6°–4.1°C) in a lower scenario (RCP4.5) and 5.8°–11.9°F (3.2°–6.6°C) in the higher scenario (RCP8.5) (high confidence).”
  • “The temperatures of extremely cold days and extremely warm days are both expected to increase.”
  • “The annual average temperature of the contiguous United States has risen since the start of the 20th century. In general, temperature increased until about 1940, decreased until about 1970, and increased rapidly through 2016.”
  • “The largest changes were in the western United States, where average temperature increased by more than 1.5°F (0.8°C) in Alaska, the Northwest, the Southwest, and also in the Northern Great Plains.”
  • “More than 95% of the land surface of the contiguous United States had an increase in annual average temperature…”


  • “The decreases in the eastern half of Nation, particularly in the Great Plains, are mainly tied to the unprecedented summer heat of the 1930s Dust Bowl era…”
  • “…there is medium confidence for detectable anthropogenic warming over the western and northern regions of the contiguous United States.”
  • “Annual precipitation has decreased in much of the West, Southwest, and Southeast and increased in most of the Northern and Southern Plains, Midwest, and Northeast. A national average increase of 4% in annual precipitation since 1901 is mostly a result of large increases in the fall season. (Medium confidence)”
  • “Heavy precipitation events in most parts of the United States have increased in both intensity and frequency since 1901 (high confidence).”
  • “The frequency and intensity of heavy precipitation events are projected to continue to increase over the 21st century (high confidence).”


  • “Projections indicate large declines in snowpack in the western United States and shifts to more precipitation falling as rain than snow in the cold season in many parts of the central and eastern United States (high confidence).”
  • “Interannual variability is substantial, as evidenced by large multiyear meteorological and agricultural droughts in the 1930s and 1950s.”
  • “For the contiguous United States, fall exhibits the largest (10%) and most widespread increase, exceeding 15% in much of the Northern Great Plains, South-east, and Northeast. Winter average for the United States has the smallest increase (2%), with drying over most of the western United States as well as parts of the Southeast.”
  • “End-of-season snow water equivalent (SWE)— especially important where water supply is dominated by spring snow melt (for example, in much of the American West)—has declined since 1980 in the western United States, based on analysis of in situ observations, and is associated with springtime warming.”
  • “There is medium confidence that anthropogenic forcing has contributed to global-scale intensification of heavy precipitation over land regions with sufficient data coverage.”


  • “…for the continental United States there is high confidence in the detection of extreme precipitation increases, while there is low confidence in attributing the extreme precipitation changes purely to anthropogenic forcing.”
  • “Although energy constraints can be used to understand global changes in precipitation, projecting regional changes is much more difficult because of uncertainty in projecting changes in the large-scale circulation that plays an important role in the formation of clouds and precip-itation.”
  • “For the contiguous United States (CONUS), future changes in seasonal average precipitation will include a mix of increases, decreases, or little change, depending on location and season…”
  • “High-latitude regions are generally projected to become wetter while the subtropical zone is projected to become drier.”
  • “As the CONUS lies between these two regions, there is significant uncertainty about the sign and magnitude of future anthropogenic changes to seasonal precipitation in much of the region, particularly in the middle latitudes of the Nation.”


  • “However, because the physical mechanisms controlling extreme precipitation differ from those controlling seasonal average precipitation, in particular atmospheric water vapor will increase with increasing temperatures, confidence is high that precipitation extremes will increase in frequency and intensity in the future throughout the CONUS.”
  • “…United States, precipitation will decrease in the spring but the changes are only a little larger than natural variations.”
  • “The Third National Climate Assessment projected reductions in annual snowpack of up to 40% in the western United States based on the SRES A2 emissions scenario in the CMIP3 suite of climate model projections.”
  • “Regional model projections of precipitation from landfalling tropical cyclones over the United States, based on downscaling of CMIP5 model climate changes, suggest that the occurrence frequency of post-landfall tropical cyclones over the United States will change little compared to present day during the 21st century, as the reduced frequency of tropical cyclones over the Atlantic domain is mostly offset by a greater landfalling fraction.”
  • “However, when downscaling from CMIP3 model climate changes, projections show a reduced occurrence frequency over U.S. land, indicating uncertainty about future outcomes.”


  • “The average tropical cyclone rainfall rates within 500 km (about 311 miles) of the storm center increased by 8% to 17% in the simulations, which was at least as much as expected from the water vapor content increase factor alone.”
  • “Recent droughts and associated heat waves have reached record intensity in some regions of the United States; however, by geographical scale and duration, the Dust Bowl era of the 1930s remains the benchmark drought and extreme heat event in the historical record (very high confidence).”
  • “While by some measures drought has decreased over much of the continental United States in association with long-term increases in precipitation, neither the precipitation increases nor inferred drought decreases have been confidently attributed to anthropogenic forcing.”
  • “The human effect on recent major U.S. droughts is complicated. Little evidence is found for a human influence on observed precipitation deficits, but much evidence is found for a human influence on surface soil moisture deficits due to increased evapotranspiration caused by higher temperatures. (High confidence)”
  • “Future decreases in surface (top 10 cm) soil moisture from anthropogenic forcing over most of the United States are likely as the climate warms under higher scenarios. (Medium confidence)”


  • “Because potential evapotranspiration increases with temperature, anthropogenic climate change generally results in drier soils and often less runoff in the long term.”
  • “However, even though it happened prior to most of the current global warming, human activities exacerbated the dryness of the soil by the farming practices of the time.”
  • “Climate model simulations suggest that droughts lasting several years to decades occur naturally in the southwestern United States.”
  • “The Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5)7 concluded “there is low confidence in detection and attribution of changes in (meteorological) drought over global land areas since the mid-20th century, owing to observational uncertainties and difficulties in distinguishing decadal-scale variability in drought from long-term trends.””
  • “…there is no detectable change in meteorolog-ical drought at the global scale.”


  • “…if a drought occurs, anthropo-genic temperature increases can exacerbate soil moisture deficits…”
  • “The absence of moisture during the 2011 Texas/Oklahoma drought and heat wave was found to be an event whose likelihood was enhanced by the La Niña state of the ocean, but the human interference in the climate system still doubled the chances of reaching such high temperatures.”
  • “This raises the question, as yet unanswered, of whether droughts in the western United States are shifting from precipitation control to temperature control.”
  • “There is some evidence to support a relationship between mild winter and/or warm spring temperatures and drought occurrence…”
  • “Due to its simplicity, the PDSI has been criticized as being overly sensitive to higher temperatures and thus may exaggerate the human contribution to soil dryness.”


  • “Seager et al. analyzed climate model output directly, finding that precipitation minus evaporation in the southwestern United States is projected to experience significant decreases in surface water availability, leading to surface runoff decreases in California, Nevada, Texas, and the Colorado River headwaters even in the near term.”
  • “In summary, there has not yet been a formal identification of a human influence on past changes in United States meteorological drought through the analysis of precipitation trends.”
  • “No studies have formally attributed (see Ch. 3: Detection and Attribution) long-term changes in observed flooding of major rivers in the United States to anthropogenic forcing.”
  • “Human activities have contributed substantially to observed ocean–atmosphere variability in the Atlantic Ocean (medium confidence), and these changes have contributed to the observed upward trend in North Atlantic hurricane activity since the 1970s (medium confidence)”
  • “Both theory and numerical modeling simulations generally indicate an increase in tropical cyclone (TC) intensity in a warmer world, and the models generally show an increase in the number of very intense TCs.”


  • “For Atlantic and eastern North Pacific hurricanes and western North Pacific typhoons, increases are projected in precipitation rates (high confidence) and intensity (medium confidence). The frequency of the most intense of these storms is projected to increase in the Atlantic and western North Pacific (low confidence) and in the eastern North Pacific (medium confidence).”
  • “Climate models consistently project environmental changes that would putatively support an increase in the frequency and intensity of severe thunderstorms (a category that combines tornadoes, hail, and winds), especially over regions that are currently prone to these hazards, but confidence in the details of this projected increase is low.”
  • “…it remains likely that global mean tropical cyclone maximum wind speeds and precipitation rates will increase; and it is more likely than not that the global frequency of occurrence of TCs will either decrease or remain essentially the same.”
  • “…the study found no evidence of a connection between the number of major U.S. landfalls from one year to the next and concluded that the 11-year absence of U.S. landfalling major hurricanes was random.”
  • “Other studies have identified systematic interdecadal hurricane track variability that may affect landfalling hurricane and major hurricane frequency.”


  • Since the 1970s, the United States has experienced a decrease in the number of days per year on which tornadoes occur, but an increase in the number of tornadoes that form on such days.”
  • “Changes in land use and land cover due to human activities produce physical changes in land surface albedo, latent and sensible heat, and atmospheric aerosol and greenhouse gas concentrations. The combined effects of these changes have recently been estimated to account for 40% ± 16% of the human-caused global radiative forcing from 1850 to present day (high confidence).”
  • “Recent studies confirm and quantify that surface temperatures are higher in urban areas than in surrounding rural areas for a number of reasons, including the concentrated release of heat from buildings, vehicles, and industry. In the United States, this urban heat island effect results in daytime temperatures 0.9°–7.2°F (0.5°–4.0°C) higher and nighttime temperatures 1.8°– 4.5°F (1.0°–2.5°C) higher in urban areas, with larger temperature differences in humid regions (primarily in the eastern United States) and in cities with larger and denser populations. The urban heat island effect will strengthen in the future as the structure, spatial extent, and population density of urban areas change and grow (high confidence).”
  • “Reducing net emissions of CO2 is necessary to limit near-term climate change and long-term warming.”
  • “Stabilizing global mean temperature to less than 3.6°F (2°C) above preindustrial levels requires substantial reductions in net global CO2 emissions prior to 2040 relative to present-day values and likely requires net emissions to become zero or possibly negative later in the century.”


  • “The IPCC estimated that 15% to 40% of CO2 emitted un-til 2100 will remain in the atmosphere longer than 1,000 years.”
  • “The persistence of warming is longer than the atmospheric lifetime of CO2 and other GHGs, owing in large part to the thermal inertia of the ocean.”
  • “…heat waves would already be significantly more severe by the 2030s in a non-mitigation scenario compared to a moderate mitigation scenario.”
 [12/12/17: Copyedits]

a rave called groundwater

I’ll be in San Diego for a groundwater (and surface water) related meeting this week. Being a major R.M. Schindler fan (an Austrian-american architect who invented California Modern), I was excited to see that there would be a tour of three of his homes on Saturday in Los Angeles, so I extended my stay a day. And then, being a major fan of Maya Jane Coles and Felix Da Housecat, I was excited to see that they will be spinning at an event in San Diego called, of all things, Groundwater! If you think about it, it all makes sense: electronic music is underground and it has a certain flow. So I’ve extended my trip yet another day cause, you know: groundwater!

(interim) Charge(s)!

[updated 1/21/18 to include the Lieutenant Governor’s specific charges on Harvey]

Between regular legislative sessions, the speaker and lieutenant governor assign tasks–called interim charges–to various committees under their purview. The speaker released a single set of charges whereas the lieutenant governor release three rounds, one specific to Harvey on September 28th,  another on October 23rd and a final on October 24th (the last two documents are dated October 23rd, but the lieutenant governors office sent press releases on the dates [23rd and 24th] indicated). Generally, charges are things for committees to look into that may or may not turn into legislation in the next session.

Many of the interim’s water charges are, not surprisingly, Harvey focused, although water resource issues–and groundwater issues–make an appearance. I’ve extracted the water-relevant charges verbatim and included them at the bottom of this post, but I’ll focus the discussion below on groundwater.

The major charge on groundwater appears for the House Committee on Natural Resources under the title “Evaluate the status of groundwater policy in Texas.” This has been a favorite topic of Chairman Larson for several years now and includes a look into aquifer-wide management, permitting, case law, brackish groundwater, data and science needs, and surface-water/groundwater interaction. Meanwhile, the Senate Committee on Agriculture, Water and Rural Affairs led by Chairman Perry has a sister charge to make recommendations to ensure that private property rights in groundwater are being sufficiently protected.

Although flooding is obviously a surface-water issue, groundwater plays a role. Even before Harvey, both water committees have been interested in capturing flood waters and injecting them into aquifers (something called aquifer storage and recovery or, more simply, ASR). Employing ASR during a flood has its challenges, namely water quality, including aquifer-clogging sediments.

Harvey affected water wells, for both water suppliers and homeowners, when water of unknown quality seeped into the aquifers (accidental ASR!). My Houston-area contacts tell me that there is not clear guidance for how to deal with wells impacted by flooding (how long to pump, how to test), so this may come up in an interim hearing as well. Further on the contamination side of things, the House Committee on Energy Resources is charged to look at plugging oil and gas wells, a particular issue in Far West Texas.

Meetings for various committees have already started. Texas Legislature Online lists future  house committee hearings and senate committee hearings. Let the policymaking begin!

House Committee on Agriculture & Livestock

1. Review the Texas Department of Agriculture’s and the Texas Animal Health Commission’s role in the response to Hurricane Harvey. Examine the short-term and long-term economic and agricultural impacts to producers in the agriculture and livestock industries in Texas as a result of Harvey. Identify ways to mitigate the impact and prevent substantial losses from Harvey and future natural disasters.

7. Evalate the uses of industrial hemp and the economic feasibility of developing an industrial hemp market under existing or future state and federal regulations. Examine the processing and manufacturing process requirements of multiple bi-products, including feed, food, fiber, cosmetics, supplements, and building materials

House Committee on Appropriations

1. Examine the use of federal funds by state agencies responding to the effects of Hurricane Harvey and identify opportunities to maximize the use of federal funds to reduce the impact of future natural disasters. Also, identify the need for state resources to respond to Harvey relief and recovery efforts, as well as opportunities for state investment in infrastructure projects that will reduce the impact of future natural disasters.

18. Monitor the agencies and programs under the Committee’s jurisdiction and oversee the implementation of relevant legislation passed by the 85th Legislature. In conducting this oversight, the Committee will also specifically monitor: a. All activities and expenditures related to Hurricane Harvey;

House Committee on Culture, Recreation, & Tourism

1. Review the Texas Parks and Wildlife Department’s and the Texas Historical Commission’s roles in the response to Hurricane Harvey. Evaluate the economic, recreational, and biological impacts and needed repairs from Harvey as they relate to applicable state agencies and the following areas and industries under the purview of the Committee:

b. Wildlife and fish

f. In addition, provide recommendations on how to allow for a timely recovery of these areas from Harvey, and how to mitigate the impact of, and adequately prepare for, future natural disasters.

2. Study the feasibility of establishing and mobilizing a volunteer contingency of private boat owners through the boat registration and license database administered by the Texas Parks and Wildlife Department to assist first responders in search and rescue efforts in natural disasters like Hurricane Harvey.

House Committee on Energy Resources

1. Examine the Railroad Commission of Texas’ (RRC) response to Hurricane Harvey. Study whether current state rules and regulations are sufficient to protect the public, natural resources, environment, infrastructure, and industrial facilities from damage caused by natural disasters. Evaluate options to ensure the availability of fuel reserves for first responders during natural disasters.

8. Monitor the agencies and programs under the Committee’s jurisdiction and oversee the implementation of relevant legislation passed by the 85th Legislature. In conducting this oversight, the Committee will also specifically consider

b. Adequacy of well-plugging processes and funds

House Committee on Environmental Regulation

1. Examine the Texas Commission on Environmental Quality’s (TCEQ) response and clean-up efforts related to Hurricane Harvey. Study whether current air, water, waste, and wastewater rules and regulations adequately protect the public, natural resources, environment, infrastructure, residential areas, and industrial facilities from damage caused by natural disasters. Evaluate the debris cleanup and removal process and whether current rules and regulations are effective in expediting cleanup efforts. Make recommendations on how natural disaster responses can be improved.

2. Examine how emergency alert systems related to hazardous and chemical releases are organized at the local, state, and federal level and explore ways to improve coordination and efficien

3. Study the permitting, siting, and regulatory processes for solid waste landfills, including municipal solid waste landfills, and whether current rules, regulations, and notice requirements adequately ensure compliance and maximize participation from the public and stakeholders.

House Committee on General Investigating & Ethics

1. Maintain oversight of federal, state, local, and charitable funds spent in response to Hurricane Harvey. Investigate instances of waste, fraud, or abuse involving such funds. Ensure that the State of Texas is maximizing federal disaster aid

House Committee on Government Transparency & Operation

1. Examine the role of technology in disaster preparedness and the response to Hurricane Harvey and future natural disasters. Review and make recommendations to drive innovation and efficiency and evaluate whether there are any regulatory impediments to collaboration between the public and private sectors.

House Committee on Homeland Security & Public Safety

1. Evaluate the response of the Texas Department of Public Safety’s (DPS) response to Hurricane Harvey. Review the actions of the Texas Division of Emergency Management and the state’s natural disaster preparedness planning efforts to determine their effectiveness at addressing Harvey-related issues. Study coordination between municipalities, counties, and state agencies and how emergency response activities are organized and coordinated at the city, county, and regional level.

House Committee on Insurance

1. Examine the effect of Hurricane Harvey on the insurance market in Texas. Include an evaluation of the status of the Texas Windstorm Insurance Association and Texas FAIR Plan Association, and of the impact of Harvey on the ability of these residual markets to achieve their statutory goals and meet the needs of their policyholders. Examine possible gaps and vulnerabilities in insurance coverage brought to light by Harvey and recommend ways to address these issues.

2. Study the coverage provided by the most common homeowners’ insurance policy forms in Texas, and methods to provide more clarity to Texas consumers about this coverage and the possible need for endorsements or other types of insurance.

House Committee on International Trade & Intergovernmental Affairs

2. Review the current state of infrastructure at Texas’ international shipping ports and border ports of entry in Texas. Identify transportation-related impediments to international trade and estimate the impact of those challenges, including border wait times, on the state’s economy. Make recommendations for improvements to facilitate international trade and economic growth. (Joint charge with the House Committee on Transportation)

House Committee on Land & Resource Management

1. Review the General Land Office’s (GLO) role and efforts during the recovery period following Hurricane Harvey. Examine the state’s readiness and protocols in response to storm-related natural disasters. Provide an assessment of public lands and make recommendations on future and ongoing mitigation strategies regarding state assets.

2. Review local and state zoning and land use regulations. Determine if current rules provide an adequate balance of disaster preparedness and deference to private property rights.

3. Examine Texas’ eminent domain statutes to ensure a balance between necessary infrastructure growth and fair compensation for landowners. Review available public information and data relating to the compensation provided to private property owners. Make recommendations to improve the accountability, as well as successful development, of the entities granted eminent domain authority.

House Committee on Natural Resources

1. Examine the following issues within the Committee’s jurisdiction regarding Hurricane Harvey and flooding in general: the role of regional entities in developing projects to control flooding, both through new infrastructure and enhancing existing infrastructure; mitigation efforts that would reduce the impact of future flood events, and strategies to fund those efforts; and the response of public entities that own or operate dams to large-scale rain events, including how such entities make decisions regarding dam and reservoir operations during such events, coordinate with state and local emergency management officials, and communicate with the public.

2. In conjunction with Charge 1, study the following additional issues related to Hurricane Harvey and flooding in general:

a. The development of the initial State Flood Plan by the Texas Water Development Board, and how the plan might be enhanced or focused in light of Harvey;

b. Science and data availability and needs related to flood risk and to responding to flood events;

c. The best methods of providing state financial assistance for flood infrastructure needs;

d. Opportunities for improved collection and storage of flood flows for future supply needs; and

e. The role of voluntary land conservation efforts, including conservation easements, in preventing and mitigating flooding.

3. Evaluate the status of groundwater policy in Texas, including the following issues:

a. Progress and challenges in encouraging coordination and consistency in aquifer-wide management and permitting practices;

b. Developments in case law regarding groundwater ownership and regulation;

c. Potential improvements to the existing groundwater permitting process, including those contemplated in H.B. 31 (85R);

d. The appropriate consideration of the service area of a water supplier when groundwater resources are allocated based on surface ownership;

e. The designation of brackish groundwater production zones and related research;

f. Groundwater data and science needs; and

g. Emerging issues in groundwater and surface water interaction, in particular in areas of increasing competition for scarce resources.

4. Examine the status of water markets in Texas and the potential benefits of and challenges to expanded markets for water.

5. Examine the potential value, the necessary elements, and the implications of a broad-based information and awareness campaign regarding water issues in Texas. Consider input from water stakeholders, educators, and communications experts.

6. Examine opportunities to enhance water development opportunities involving neighboring states and Mexico. Evaluate lessons from previous attempts to import new water supplies, as well as the impacts of noncompliance with the 1944 treaty with Mexico on the Rio Grande Valley region.

7. Analyze the need to update Water Availability Models for the river basins in this state.

8. Study the hazards presented by abandoned and deteriorated groundwater wells, and make recommendations to address the contamination and other concerns these wells may represent.

9. Examine opportunities to enhance water development opportunities involving neighboring states and Mexico. Evaluate lessons from previous attempts to import new water supplies, as well as the impacts of noncompliance with the 1944 treaty with Mexico on the Rio Grande Valley region.

House Committee on Special Purpose Districts

1. Evaluate the impact of Hurricane Harvey on residential communities within special purpose districts and districts’ capacity to respond. Review the role and adequacy of the districts in emergency preparedness and response. Make recommendations for strengthening districts’ emergency operations.

2. Review the statutes and procedures related to state approval and oversight of water district bonds that finance utility, infrastructure, and other projects. Identify opportunities for improving the state’s oversight of bond issuance and make recommendations for statutory changes.


Senate Committee on Agriculture, Water, and Rural Affairs

Study and make recommendations on how to move forward with water infrastructure projects in the State Water Plan that will help mitigate floods through flood control, diversion, and storage projects. Evaluate plans for a possible third reservoir in addition to Addicks and Barker to control and alleviate additional flooding in the region. Additionally, review the current status of reservoir projects in Texas. Examine opportunities for coordination between federal and state agencies to develop flood mitigation infrastructure, and the ongoing maintenance and restoration of critical dam infrastructure.

Study and identify ways to improve the capacity and maintain the structure of the Addicks and Barker Reservoirs. Report on mechanisms that would ensure the public has access to timely and transparent release figures from reservoirs across the state.

Evaluate current state data-sharing standards for rainfall and stream gauges and whether regional flood management projects and flood warnings should be hosted in a centralized location, such as a state agency web page. Determine whether a statewide real-time flood warning system could be developed and coordinated through mobile devices, TxDOT electronic signage, communication devices and whether existing local and regional forecasting infrastructure could be integrated into a centralized inclement weather forecasting system.

Streamlining Water Permitting: Study and recommend changes that promote streamlining of water right permit issuance and the amendment process by the TCEQ for surface water, and that promote uniform and streamline permitting by groundwater conservation districts for groundwater. Evaluate more transparent process needs and proper valuation of water.

Regulatory Framework of Groundwater Conservation Districts and River Authorities: Study and make recommendations on the regulatory framework for managing groundwater in Texas to ensure that private property rights are being sufficiently protected. Study the role of river authorities and groundwater conservation districts including the state’s oversight role of their operations and fees imposed.

Monitoring: Monitor the implementation of legislation addressed by the Senate Committee on Agriculture, Water & Rural Affairs during the 85th Legislature, Regular Session, including, but not limited to: SB 1511 (prioritization in the regional water plan); SB 1538 (Floodplain Management Account uses); SB 864 (GCD application of state water); HB 2004 (Texas economic development fund for TDA); and HB 3433 (adoption of rules affecting rural communities. Make recommendations for any legislative improvements needed to improve, enhance, or complete implementation including regional water planning, flood planning, and groundwater production.

Senate Committee on Business and Commerce

Study infrastructure security and energy restoration post weather events. Identify ways state government entities can help utilities more effectively stage pre- hurricane mobilization crews for managing resources before an event.

Examine state mortgage requirements regarding the notification of homebuyers on their need for flood insurance in flood plains and flood pool areas and make recommendations on how to better inform consumers.

Examine and make recommendations on the need for changes to the Texas Constitution for home equity lenders to offer various forms of relief to Texas homeowners affected by natural disasters including, among others, the authority to enter into deferment agreements. This examination should include a study of home equity rules regarding negotiation, modification and refinancing and whether constitutionally established time periods can be waived in times of disasters.

Senate Committee on Finance

Evaluate the long-term impact of Hurricane Harvey on the Texas economy and the gulf coast region.

Senate Committee on Health and Human Services

Review the state’s response to Hurricane Harvey with a focus on public health efforts at the local and state level. The review should include an analysis of the state and local response related to vector control, immunization needs, utilization of health-related volunteers, adequacy of an emergency medical network, evacuation of vulnerable populations from state operated or regulated facilities, and coordination between all levels of government. Recommend any legislative changes necessary to improve public health response and coordination during and after a disaster.

Senate Committee on Intergovernmental Relations

Special Purpose Districts Bond Reform: Study the state agency review of tax exempt bonds issued by special purpose districts and public improvement districts used to finance water and sewer infrastructure in new residential and commercial developments. Examine the disparities that exist between the feasibility review of water and sewer bonds backed by property-based assessments and those backed by ad valorem taxes, and make recommendations that ensure the continued stability of the Texas tax-exempt bond market by requiring all districts to undergo appropriate reviews prior to issuance.

Senate Committee on Natural Resources and Economic Development

Environmental Safety: Study the strategies and best practices for ensuring environmental safety during maintenance, startup, and shutdown activities due to emergencies. Recommend actions to improve safety without compromising compliance or penalizing good actors.

Senate Committee on State Affairs

Review the interaction between federal, state, and local agencies in charge of responding to natural disasters. Examine emergency situation operations, including evacuation routes and procedures, and the efficient use of Disaster Recovery Centers. Make recommendations to ensure emergency management officials have the tools and authority necessary to promptly and appropriately respond to disaster areas and alert citizens to potential threats.

Study and make recommendations on the benefit of the state maintaining a single, web-based source of comprehensive information that outlines the State Emergency Operations during times of disaster.

Senate Committee on Veterans Affairs and Border Security

Border – Invasive Species: Study and make recommendations on the impact to border security caused by invasive plant species, such as carrizo cane and salt cedar. Review proposals for eradication of invasive plant species that provide a natural shelter for human trafficking and/or smuggling arms and illicit substances.


(license-free image from Pexels)

do computers dream of groundwater?

Recent articles note that an artificial intelligence program named CARMEL is not only trying to decrypt notes from the Zodiac Killer but is also writing poetry on the side. I decided to see what CARMEL had to say, poetically speaking, about groundwater:


Water constellations chronic low!
With mushroom market Morrison formation!
Can hear collecting conversations flow,
Boiling underground contamination.

Cotton pavement painted gravel sand,
They handle human concentration drains.
A self-destruction hurricane O grande!
The stockings slaughtered under gravel plains.

Construction children screaming tooth decay!
A hundred billion dollar bearer channel,
Prescription pictures over boulder clay,
Water watching water table gravel.

A face of accidental injury,
Throughout the neighborhood utility.

Water Table

Cathedral crawling ceiling valley floor!
The corner drinking plastic coffee maker.
An engine shooting screaming oven door,
Night transmission sleeping surface layer.

Marble kitchen table throwing ice,
Surroundings breathing bottom dollar dipping!
Dismembered stomach smoking loaded dice,
Construction motorcycle motor filling.

Prescription swimming supermarket feeding!
Spaghetti self-destruction large enough!
Of chocolate water eating chicken steaming,
Vanilla leather dripping Bishop tuff.

A breakfast table spreading Sandy soil,
Beneath the water boiling water boil.


Formaldehyde police Professor ar.
An orange plastic politician error,
Mushroom mountainside de Santa mar!
A headless human sensitive detector.

A burning constellation Roger bacon!
Congratulations Persian calendar!
Outstretched construction hostage situation,
The sleeping self-destruction tank commander.

Policeman scratching on Omega T,
Breathing boiling water rigid body!
Machine transmission television V,
A Russian rollercoaster drinking Donnie.

Computer captain English racing driver,
The table walking water mountain biker.

Desired Future Condition

Fulfilling final transformation may,
A nation under total expectation!
Controlling consciousness without delay!
Of human conversation realization.

A surface spent extremely time-consuming,
Collective sickness seeking sinful nature.
Computer confidence conditioned choosing,
Dismembered individual behavior.

Another rule and only one decision!
Construction confrontation you must wait!
Misplaced prescription physical condition,
Reflections through the total terminate.

A voice of understanding necessary,
Afraid of self-destruction something any.