Every once in a while a factoid crosses the desk and/or mind of an otherwise badly-informed person who denies global warming is a problem, and without bothering to check the significance of the factoid, the denialist world ramps up The Crazy Rant.
And so, Steve Goddard (who should need no introduction) seized upon a chart that shows a momentary uptick in water in drought-ravaged Lake Powell. Ignoring more than 50 years of history of the river flows, Goddard pronounced the case for global warming dead.
Former AGW poster child Lake Powell water levels have been rising rapidly over the last few years.
Goddard’s claim is a grand example of the triumph of ignorance over experience, science, data, history and the law, in discussions of climate change.
Did Goddard read his own chart? It shows a decline in lake level from 2010.
“Full pool” level is 3,700 feet elevation (the height of the surface of Lake Powell above sea level). Goddard’s chart shows the lake hasn’t been at that level since 2000 (and it was declining for some time prior to that). Goddard’s chart shows four years of rise compared to seven years of decline.
Upper Colorado River Basin Hydrology
In the Upper Colorado River Basin during water year 2010, the overall precipitation accumulated through September 30, 2010 was approximately 90% of average based on the 30 year average for the period from 1971 through 2000. For Water Year 2011 thus far, the estimated monthly precipitation within the Upper Colorado River Basin (above Lake Powell) as a percentage of average has been: (October – 135%, November – 95%, December – 225%, January – 50%, February – 100%, March – 90%)
The Climate Prediction Center outlook (dated March 17, 2010) for temperature over the next 3 months indicates that temperatures in the Upper Colorado River Basin are expected to be above average while precipitation over the next 3 months is projected to be near average in the northern reaches of the basin while below average in the southern reaches of the basin.
Upper Colorado River Basin Drought
The Upper Colorado River Basin continues to experience a protracted multi-year drought. Since 1999, inflow to Lake Powell has been below average in every year except water years 2005 and 2008. In the summer of 1999, Lake Powell was close to full with reservoir storage at 23.5 million acre-feet, or 97 percent of capacity. During the next 5 years (2000 through 2004) unregulated inflow to Lake Powell was well below average. This resulted in Lake Powell storage decreasing during this period to 8.0 million acre-feet (33 percent of capacity) which occurred on April 8, 2005. During 2005, 2008 and 2009, drought conditions eased somewhat with near or above average inflow conditions and net gains in storage to Lake Powell. 2011 will be another above average inflow year so drought conditions are easing somewhat in the Colorado River Basin. As of April 18, 2011 the storage in Lake Powell was approximately 12.73 million acre-feet (52.3 % of capacity) which is below desired levels. The overall reservoir storage in the Colorado River Basin as of April 18, 2011 is approximately 31.40 million acre-feet (52.8 % of capacity).
Updated: April 19, 2011
Goddard isn’t the first denier to stumble down this path — but can’t they learn from the stumblings of others? Remember Australia’s “Jo Nova,” who used a photograph of drought-stricken Glen Canyon Dam and environs to claim that warming was not posing problems? Remember Anthony Watts claiming Lake Powell as a “good proxy” for water in the entire area, and seizing on a momentary uptick? (Oh, yeah — Watts based his glee on a Goddard note — even repeating Goddard’s error that Lake Powell’s low levels were due to increased use of water in Los Angeles . . .)
Oy. Do they ever learn?
The sources from my earlier post on Lake Powell still edify those who bother to read them:
- Dead Pool: Lake Powell, Global Warming, and the Future of Water in the West,James Lawrence Powell, University of California Press 2009. Review of Dead Pool by David Jenkins at Electronic Green Journal. Note at USC News. Note from Lawrence at the UC Press site.
- Down to the Wire: Confronting Climate Collapse, David Orr, Oxford University Press 2009.
- Press release from National Parks Traveler, April 7, 2008, “Lake Powell expected to rise 50 feet this summer,” noting that record snowfalls were expected to refill Lake Powell partially. (See the editorial linked below — 50 feet wasn’t enough.)
- “Lakes Mead and Powell could run dry by 2021,” Christian Science Monitor, February 13, 2008; cites study by Scripps Institution of Oceanography; Scripps Institution press release on the study; the paper was published in Water Resources Research, a peer-reviewed journal.
- “Desert mirage,” editorial discussion of Lake Powell’s climate-change-fueled dropping levels threatening a water project for St. George, Utah, with discussion of U.S. Research Council report on future levels of Lake Powell; Salt Lake Tribune, January 6, 2010. “Lake Powell’s current water level is 59 percent of capacity. The lake level, around 20 million acre-feet in 2000, dropped to about 8 million acre-feet by 2005. Water levels rebounded a bit over the next two years, but the U.S. National Research Council predicted in 2007 that the American West could see worse droughts in the future than the one Utahns experienced from 1998 to 2005. In fact, the early 20th century, when the Colorado compact was negotiated, was an anomaly, a relatively wet period for an otherwise historically much drier area.”
More current sources:
- Snow pack in the Upper Colorado drainage
- BuRec says very large snow pack is enough to avert shortages in the Lower Colorado, this year — but the drought continues: “The Colorado River Basin has experienced historic drought, and while this winter’s snowpack will benefit river flows, we cannot say that the drought is over,” cautioned Commissioner Connor. “Given the potential for extended dry years, and the effects of climate change on snowpack and runoff in the Colorado Basin, we must continue to work with the states, tribes and other stakeholders in the Basin to meet the water needs in the future.”
- New York Times Green Blog, “A reprieve for Western Water users”; “What if this year is an anomaly — not like the year 1983, a gusher of a rain year that was followed by four more fat years, but like the other above-normal years that came and went in the last decade without really denting the impact of the long-term drought?”