“A top climate scientist warned [in October 2007] that Texas faces a dual threat from floods and drought if global warming is left unchecked.”  Additionally, “scientists’ computer models indicate that the pattern of drier weather has already begun.”

Texas almost certainly faces a future of perpetual drought as bad as the record dry years of the 1950s because of global warming, climate scientists said in a study published Thursday [April 5, 2007].

The trend toward a drier, hotter southwestern U.S., including all of Texas, probably has already begun and could become strikingly noticeable within about 15 years, according to a study led by Richard Seager of Columbia University’s Lamont-Doherty Earth Observatory.

Drought conditions are expected to resemble the Dust Bowl years of the 1930s and Texas’ worst-ever drought of the 1950s, Dr. Seager said.  Unlike those droughts, however, the new conditions won’t be temporary, the study found.

The warning is bleak: Prepare for an “imminent transition to a more arid climate.”

“In 2006, drought-related crop and livestock losses were the state’s worst for a single year, totaling $4.1 billion.”  In July 2007, “the state was declared drought-free for the first time in at least a decade” following the “wettest January to August period on record…”  By February of the following year, however, and despite “hurricanes Dolly, Gustav and Ike soaking Texas in 2008, almost every part of the state — nearly 97% — [was once again] experiencing some drought…”

Just this past week “it was noted that the most recent rains over the last several months have had little to no impact on the hydrology in the state, with rivers, streams, and reservoirs lagging as some locations have had improvements.  Many changes were made across the state this week, with [abnormally dry and moderate drought] expanded in the northern panhandle, [severe drought] improved in the southern tip of the state, [severe drought, extreme drought and exceptional drought] expanded in south central Texas, and [abnormally dry] expanded in central Texas.  Even in areas where some good rains fell during the spring months, agricultural and hydrological concerns are still having issues related to the long-term dryness in the region.”

In fact, “drought conditions … are so bad cattle are keeling over in parched pastures and dying.”  State agriculture officials pointed out in March 2009 “that ranchers in the nation’s largest cattle-producing state [had] already lost nearly $1 billion because of [the] ongoing drought.”

But what of nature’s own, the flora and fauna in the state?  Of more than 800 bird species in the U.S., “the official Texas State List [contains] 632 species in good standing,” and of “the 338 [bird] species that are listed as Nearctic-Neotropical migrants in North America (north of Mexico), 333 of them (or 98.5%) have been recorded in Texas.”  The state provides the only migratory route for the entire eastern population of monarch butterflies.  More species of North America’s wild cats live in Texas than anywhere else north of the Mexico border.  93 endangered species reside in the state.

“The lack of rainfall means freshwater marshes … that were inundated by Hurricane Ike are not being flushed of salt water.  That lack of flushing is killing plants and damaging soil chemistry.”

“…[W]ildlife die-offs of whooping cranes and deer have been reported.”  This past winter “the only migrating whooping-crane flock that exists in the wild lost 23 of its 270 members to hunger and disease brought on by the dry weather, said Tom Stehn, U.S. Fish and Wildlife Service whooping-crane coordinator.”  And that loss came despite “the fact that the cranes’ diet was supplemented for the first time in 60 years…”

“…[L]ittle fresh water is available for use by mottled duck broods, and that will likely lead to a very low production of mottled ducks this season. […] They’ve been declining for the past 30 years due to habitat loss and other factors, so drought effects are adding stress to an already stressed population.”

“…[A]lligators and amphibians are unable to recolonize areas inhabited before Hurricane Ike because of the salt water, and populations of these animals will likely remain depressed for the next several years.”

“Lack of salt-flushing winter rains along the upper and middle Texas coast have much delayed recovery of wetlands hit hard by Hurricane Ike and could … negatively impact health of estuaries crucial to marine life.”

“The coastal fishing industry also has been hit hard as salty conditions shrink populations of shellfish such as oysters and crabs.”

“Siltation from Ike smothered approximately 60 percent of Galveston Bay’s oyster beds.  Increased salinity caused by lack of freshwater runoff from rivers allows salinity-loving predators such as oyster drills and ‘dermo’ to prey upon remaining oyster beds.”  “Any further loss of oysters will have a hugely detrimental impact on the bay’s ecosystem…”

“…[T]here were reports of non-native axis deer dying from starvation coupled with cold weather earlier this year.  TPWD wildlife biologists report range conditions are in poor shape, prickly pear is thin because of the lack of water and feral hogs are looking very thin and drawn down.”

“…TPWD wildlife biologists observed a considerable drop in the pronghorn antelope population…”

“Dry conditions threaten to negatively impact wildlife because of a lack of forage and cover from which to avoid predation.  Lack of ground cover could significantly limit nesting efforts of ground-nesting birds such as turkey and quail and reduce survival of deer fawns.”  “Native whitetail deer still appear in decent condition but may not last long if the situation continues.”

“If parts of Texas remain parched, particularly the south, experts say Rio Grande turkey breeding activity and nesting effort will be greatly reduced or nonexistent.”

“[T]he bare ground — a lot of it covered only with dirt and rock — can’t support the microorganisms and insects that form the base of the food chain.”

This spring has resulted in “minimal rebounding of the ‘good’ vegetation necessary to support thriving natural systems.”

“Even weeds are having a hard time flourishing.”

— — — — — — — — — —

Sources:
Houston Chronicle (1, 2)
Associated Press (1, 2, 3, 4)
NOAA
U.S. Drought Monitor
Dallas Morning News
Lamont-Doherty Earth Observatory at Columbia University
Texas Parks & Wildlife Department (1, 2)
Texas Birds Records Committee
Wild Cat Species of North America
The Wall Street Journal

Photos:

[1] Black-necked stilt (Himantopus mexicanus) hunting in what remains of the freshwater ponds; the newly exposed ground is covered with crystallized salt

[2] American alligator (Alligator mississippiensis) trying to remain submerged in what has become a salty mud puddle; a dozen alligators once occupied this brackish pond; now there’s barely room for one—and a juvenile at that

[3] Male chital (a.k.a. cheetal, chital deer, spotted deer, or axis deer; Axis axis) searching for food on barren ground; half the trees in this area are dead

[4] Pregnant white-tailed deer (Odocoileus virginianus) grazing in front of the refuge’s administrative buildings; I worry for her offspring’s future

[5] Female pipevine swallowtail butterfly (Battus philenor) laying eggs on a dying sprout; no pipevine (Aristolochia sp.) could be found by me or by the butterflies, so her eggs will probably give rise to caterpillars that will starve

[6] Yellow-bellied bee assassin (Apiomerus flaviventris) in search of food; with so few insects at a time when they should be plentiful, this predator will have a hard time locating sustenance

[7] Great southern white butterfly (Ascia monuste) feeding from bushy seaside tansy (a.k.a. sea ox-eye; Borrichia frutescens); the shrub now fills what used to be a salt marsh full of blue crab

[cross-posted to The Clade]

[Update] David Crossley brought to my attention an incorrect date reference in the original text.  That reference has been corrected.