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October 6th, 2022
Via Grand Junction Sentinel, commentary on the relationship between water and politics:
The most important long-term issue for Colorado today is the same as it was 120 years ago… water. In 2010, Smithsonian Magazine published an article titled, “The Colorado River Runs Dry.” The article included a quotation from Brad Udall of Colorado State University, “Climate change will likely decrease the river’s flow by 5% to 20% in the next 40 years.” On Aug. 25, 2022, Udall told the Steamboat Pilot and Today, “This isn’t a drought, it’s something else. … Myself and other scientists are trying to use a different term: Aridification.” In defining aridification he said, “declining snow-packs, it’s earlier runoff, it’s a shorter winter, it’s more rain, less snow, it’s higher temps. It’s drying soils, it’s severe fires, it’s forest mortality, it’s a warm, thirsty atmosphere.” The only issue with this quote is it is mostly erroneous. There is a slight warming trend since 1993; thus, the atmosphere holds more moisture and precipitation is on a slight incline.
There is a reason the Southwest is called the “desert southwest.” With the exception of the Rocky Mountains, it does not rain out here very much. The USDA records the average annual precipitation in the Rockies at 21-40 inches per year between 1961 and 1990, with over 50 inches being common. The decadal average precipitation throughout the basin has not changed since 1901, with the last decadal average being 2011-2019. The highest precipitation for Denver was 16.18 inches (1991-2000) and the lowest was 12.8 inches (1931-1940). Not much variation over the past 100+ years. Bottom line: precipitation across the Colorado River basin is not declining and thus the river is not “drying up”… at least not in the upper basin.=
Does that mean there is no water crisis? No. There is a crisis, but it is not caused by climate change or drought or “aridification.”
If you Google Colorado River, you will find pages of popular articles projecting doom and gloom for the river. These articles are all long on anecdotes (i.e., stories/reminiscences) and emotion, but very short on facts. I cited the decadal averages for precipitation earlier; this “climate” data proves there is no alarming trend. So, what about temperature?
Since I only get 750 words for this article, I will focus only on Colorado. The following data is from all ground-based weather stations in Colorado and represents the state average maximum temperature. If we start at 1993, then Colorado maximum temperature has increased 3 degrees Fahrenheit. If we stopped there, it would be alarming. But, if we start with 1931, Colorado has cooled 2 degrees Fahrenheit. The graph of data from 1901 to 2022 shows a slight cooling trend. The average in 1901 was 3 degrees Fahrenheit warmer than 2022. Bottom line: average temperature in Colorado shows no strong warming (or cooling) trend over the last 120 years.
So, what gives? The data for precipitation and temperature is all good news. The crisis, however, is starkly clear when one looks at the water levels at Lake Powell and Lake Mead.
If a popular article includes data, it is usually concerning the water level at these huge reservoirs that store water for Phoenix, most of Arizona, Las Vegas, Los Angeles, San Diego and Southern California. Hence, the cause of the problem: people and politics.
The flow rate of the upper basin, when adjusted for human off-take (mainly municipalities, cities and agriculture) fluctuates cyclically, but the long-term trend is virtually unchanged. In the “old” days, the primary demand for river water was agriculture. What has changed is the number of city dwellers now needing water.
Phoenix has grown 432% since 1970. Las Vegas is up 1,082% since 1970; Los Angeles is up 49% or 4.1 million and Denver up 174%.
Bottom line: Lake Powell and Lake Mead levels are down because of population growth, primarily in the lower basin. Water demand has exceeded the normal replenishment rate in Lake Mead. River flow rate into Lake Powell, adjusted for human off-take, is normal. The climate change boogieman is not to blame.
Peter Gleick, Pacific Institute, told the LA Times that scientists’ have warned politicians and water management bureaucrats for years. He was an author of one of these early warnings in 1993, 30 years ago. “If we had cut water use in the Colorado River over the last two decades to what we now understand to be the actual levels of water availability, there would be more water in the reservoirs today,” Gleick said. “The crisis wouldn’t be nearly as bad.” Notice, he did not blame climate change.
The scientists, “experts,” politicians and water bureaucrats have the data I have reviewed.