This is a partial re-post from Texas Climate News
Off the chart: The new National Climate Assessment contains numerous references to Texas' record-setting heat and drought in 2011. Those harsh conditions – the large red dot on this chart – "represent conditions far outside those that have been registered since the instrumental record began" in the 19th century, the report says. "Generally," it adds, "the changes in climate are increasing the likelihood for these types of severe events."
By Bill Dawson
Texas Climate News
Expert authors: 240. Number of pages: 1,146.
Those two numbers convey a sense of the scope of the scientific effort that went into a new federally-comissioned report on climate change, issued last month in draft form. The study “collects, integrates, and assesses observations and research from around the country, helping to show what is actually happening and what it means for peoples’ lives, livelihoods, and future.”
The first paragraph of the National Climate Assessment – the first updated edition of that congressionally-ordered study in four years – conveys a sense of its sweeping findings:
Climate change is already affecting the American people. Certain types of weather events have become more frequent and/or intense, including heat waves, heavy downpours, and, in some regions, floods and droughts. Sea level is rising, oceans are becoming more acidic, and glaciers and arctic sea ice are melting. These changes are part of the pattern of global climate change, which is primarily driven by human activity.
Katharine Hayhoe, director of the Climate Science Center at Texas Tech University and a lead author of one chapter in the report, told the Associated Press: “There is so much that is already happening today. This is no longer a future issue. It’s an issue that is staring us in the face today.”
And it will continue to do so in coming years and decades, the report stresses:
Human-induced climate change is projected to continue and accelerate significantly if emissions of heat-trapping gases continue to increase. … Climate change threatens human health and well-being in many ways, including impacts from increased extreme weather events, wildfire, decreased air quality, diseases transmitted by insects, food, and water, and threats to mental health.
What does – and will – it mean for Texas? The report has no single, comprehensive, state-level appraisal, per se, but one way to get a general idea of what it says on that question is to glean it from maps and other graphics that illustrate many of the key conclusions and projections included by the authors.
TCN reviewed the report’s 1,146 pages to assemble this selection of graphics with Texas-related information. (Captions beneath the graphics reproduced below also appear in the report.)
+++ Temperature +++
U.S. temperature change: 1991-2011 vs. 1901-1960
Most of Texas has been growing warmer over the past two decades – less so than many parts of the country, but more than some Southeastern states.
Temperature projection: 2070-2099
In the 2070-2099 period, compared to 1971-1999, average surface air temperatures in Texas are projected to be 3 to 5 degrees F warmer if there are “substantial reductions in heat trapping gases” and 6 to 9 degrees F warmer in a higher-emission scenario.
More AC-conducive days
Texans use a lot of air conditioning already. A study projected a considerably greater increase in the state in “cooling degree days” (when people tend to use air conditioning) with higher emissions of greenhouse gases.
+++ Drought and water +++
Drought severity
Droughts would grow more damaging in Texas under this 2011 projection, though not by as much as in parts of Mexico and in areas of the U.S. to the north and northwest of the state. Lower numbers on the standard Palmer Drought Severity Index indicate drier conditions.
“Dry days”
In a contrast with Plains states to the north, Texas is projected to experience more “dry days” – those with less than a tenth of an inch of precipitation – more so if greenhouse emissions continue to rise (map at right) than in a scenario with “substantial reductions.”
For more, click here to re-direct to the full Texas Climate News post
Posted by dana1981 on Friday, 26 July, 2013
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