A new U.S. Geological Survey study finds, “Warmer spring temperatures since 1980 are causing an estimated 20 percent loss of snow cover across the Rocky Mountains of western North America.”
The USGS explains, “The new study builds upon a previous USGS snowpack investigation which showed that, until the 1980s, the northern Rocky Mountains experienced large snowpacks when the central and southern Rockies experienced meager ones, and vice versa. Yet, since the 1980s, there have been simultaneous snowpack declines along the entire length of the Rocky Mountains, and unusually severe declines in the north.”
We reported on that previous work in 2011 — see “USGS: Global Warming Drives Rockies Snowpack Loss Unrivaled in 800 Years, Threatens Western Water Supply.” The USGS explained back then:
The warming and snowpack decline are projected to worsen through the 21st century, foreshadowing a strain on water supplies. Runoff from winter snowpack – layers of snow that accumulate at high altitude – accounts for 60 to 80 percent of the annual water supply for more than 70 million people living in the western United States.
What’s most worrisome is that we now have three major trends driven by human emissions of greenhouse gases that threaten to significantly worsen drought and water problems in the West and Southwest:
- Less precipitation in many areas (see here)
- Less snowpack, as the USGS studies have found
- Hotter temperatures (see “We’re Already Topping Dust Bowl Temperatures — Imagine What’ll Happen If We Fail To Stop 10°F Warming“).
Assuming the anti-science crowd continue to block any serious action, these catastrophic changes will last a long, long time (see NOAA: Climate change “largely irreversible for 1000 years,” with permanent Dust Bowls in Southwest and around the globe).
For the record, it was the possibility of losing the Sierra snowpack in the second half of the century that led then Energy Secretary Chu to warn in 2009, “Wake up,” America, “we’re looking at a scenario where there’s no more agriculture in California.”
Geophysical Research Letters published the new research, “Regional patterns and proximal causes of the recent snowpack decline in the Rocky Mountains” (subs. req’d). Here are the key points from the USGS news release:
The new study has teased apart and quantified the different influences of winter temperature, spring temperature, and precipitation on historic snowpack variations and trends in the region. To distinguish those varying influences, the researchers implemented a regional snow model that uses inputs of monthly temperature and precipitation data from 1895 to 2011.“Each year we looked at temperature and precipitation variations and the amount of water contained within the snowpack as of April,” said USGS scientist Greg Pederson, the lead author of the study. “Snow deficits were consistent throughout the Rockies due to the lack of precipitation during the cool seasons during the 1930s – coinciding with the Dust Bowl era. From 1980 on, warmer spring temperatures melted snowpack throughout the Rockies early, regardless of winter precipitation. The model in turn shows temperature as the major driving factor in snowpack declines over the past thirty years.”… The timing of snowmelt affects not only when water is available for crop irrigation and energy production from hydroelectric dams, but also the risk of regional floods and wildfires. Earlier and faster snowmelt could have repercussions for water supply, risk management, and ecosystem health in western watersheds.… [Greg] McCabe, co-author of the study, explains that “recent springtime warming also reduced the extent of snow cover at low to middle elevations where temperature has had the greatest impact.”
What’s particularly worrisome is that we’ve seen these dramatic and harmful changes already — and we’ve only warmed about a degree and a half Fahrenheit in the past century. The problem for our children and grandchildren is that if we continue anywhere near our current greenhouse gas emissions pathway, we are on track to warm five times times that or more this century (see “An Illustrated Guide to the Science of Global Warming Impacts: How We Know Inaction Is the Gravest Threat Humanity Faces“).
Another 2011 study, “The Last Drop: Climate Change and the Southwest Water Crisis,” found that drought and reduced precipitation in the U.S. SW alone could cost up to $1 trillion by century’s end.
The time to act was a long time ago, but now is still better than later.
http://thinkprogress.org/climate/2013/05/16/2008091/us-geological-survey-warmer-springs-causing-loss-of-snow-cover-throughout-the-rocky-mountains/?mobile=nc
Into The Valley Of Death Rode The 600, Into The Valley Of 400 PPM Rode The 7 Billion
“Forward, the Light Brigade!”
Was there a man dismay’d ?
Not tho’ the soldier knew
Some one had blunder’d:
Theirs not to make reply,
Theirs not to reason why,
Theirs but to do & die,
Into the valley of Death
Rode the six hundred.– “The Charge Of The Light Brigade,” Alfred, Lord Tennyson, 1854
How will poets memorialize us? How will we be remembered if, like the British light cavalry charging a well-prepared Russian artillery battery in the Crimean War in 1854, we don’t reason why, we just keep on our current path even though it is self-evidently suicidal.
CO2 levels for past 12,000 years and projected to 2100 assuming no change in policies (via Koomey)
“It may seem impossible to imagine that a technologically advanced society could choose, in essence, to destroy itself, but that is what we are now in the process of doing.” So ends Field Notes from a Catastrophe, the terrific 2006 book by Elizabeth Kolbert, one of the country’s most thoughtful climate journalists.
Certainly as we hit 400 parts per million (ppm) for the first time in human existence, with not even a plan to avoid 600 ppm, 800 ppm, and then 1000 — not even a national discussion or an outcry by the so-called intelligentsia – it is worth asking, why? Is there something inherent in homo “sapiens” that makes us oblivious to the obvious?
In his latest analysis, uber-hedge fund manager Jeremy Grantham points us in the direction of a new book, Immoderate Greatness: Why Civilizations Fail, by William Ophuls. Grantham, a self-described “die hard contrarian,” is one of the few leading financial figures who gets both global warming and growing food insecurity (see “Welcome to Dystopia”: We Are “Entering A Long-Term And Politically Dangerous Food Crisis“).
Ophuls’ treatise, a synthesis of various analyses for civilizations fail, is well worth reading, though it isn’t a sunny book. Grantham’s analysis is a short, marginally-more optimistic version of the book, augmented with his own thinking. Grantham begins:
The Fall of CivilizationsThe collapse of civilizations is a gripping and resonant topic for many of us and one that has attracted many scholars over the years. They see many possible contributing factors to the collapse of previous civilizations, the evidence pieced together shard by shard from civilizations that often left few records. But some themes reoccur in the scholars’ work: geographic locations that had misfortune in the availability of useful animal and vegetable life, soil, water, and a source of energy; mismanagement in the overuse and depletion of resources, especially forests, soil, and water; the lack of a safety margin or storage against inevitable droughts and famines; overexpansion and costly unnecessary wars; sometimes a failure of moral spirit as the pioneering toughness and willingness to sacrifice gave way to softer and more cynical ways; increasing complexity of a growing empire that became by degree too expensive in human costs and in the use of limited resources to justify the effort, until the taxes and other demands on ordinary citizens became unbearable, so that an empire, pushed beyond sustainable limits, became vulnerable to even modest shocks that could in earlier days have been easily withstood. Probably the greatest agreement among scholars, though, is that the failing civilizations suffered from growing hubris and overconfidence: the belief that their capabilities after many earlier tests would always rise to the occasion and that growing signs of weakness could be ignored as pessimistic. After all, after 200 or even 500 years, many other dangers had been warned of yet always they had persevered. Until finally they did not.The bad news is that as I read about these varied scenarios – and I have missed listing several – they all appear plausible and each seems to be relevant to several earlier collapses of empires and civilizations both large and small. Very recently, one of these scholars, William Ophuls, wrote a new book, Immoderate Greatness (a quote from Gibbons’s Decline and Fall of the Roman Empire), with the subtitle Why Civilizations Fail. It is a straightforward summary and synthesis of all of the ways to fail in 70 small pages, yet with extensive notes and references. It is written in remarkably accessible, simple language and divides the causes of failure into six categories. Unfortunately, all six seem to apply to us today in varying degrees, and where one factor might be manageable – although often has not been – he makes the chances of our managing all six seem slight. It is persuasive and needs to be read. It takes about two hours.William Ophuls’s conclusion is that we will not resist the impressive list of erosive factors and that, in fact, we are in the fairly late stages of our current civilization’s race for the cliff edge with nothing much to head us off. His study of history leads him to believe that civilizations are actually hard wired to self-destruct: programmed to be overconfident, to keep on pushing for growth until limits are overstepped and risks accumulated to the breaking point. His offer of good news is that after the New Dark Ages, when civilization again rears its head, presumably with a much smaller population, we will have acquired the good sense to be less overreaching, less hubristic, a lot humbler about growth and our use of resources, and more determined to live in balance with the natural energy we receive from the sun and the heat, food, and water with which we can sustainably be provided.
Humanity isn’t making a suicidal charge into an artillery brigade, of course. And what we are accelerating toward is less a cliff than a brick wall — but it is no less self-evident how self-destructive it is:
Temperature change over past 11,300 years (in blue, via Science, 2013) plus projected warming this century on humanity’s current carbon pollution emissions path (in red, via recent literature).
Wikipedia says of the infamous charge, “The semi-suicidal nature of this charge was surely evident to the troopers of the Light Brigade, but if there was any objection to the orders, it was not recorded.” How like Wikipedia to try to deglamorize the whole thing!
I fear our generations’ Wikipedia entry will read much the same. But one can hold out a hope that future generations, when they are done cursing our names, will think we are at least worth a good poem … though not, I think, one celebrating our benighted honor:
http://thinkprogress.org/climate/2013/05/05/1940521/into-the-valley-of-death-rode-the-600-into-the-valley-of-400-ppm-road-the-7-billion/Cannon to right of them,
Cannon to left of them,
Cannon behind them
Volley’d and thunder’d;
Storm’d at with shot and shell,
While horse & hero fell,
They that had fought so well
Came thro’ the jaws of Death,
Back from the mouth of Hell,
All that was left of them,
Left of six hundred.When can their glory fade?
O the wild charge they made!
All the world wonder’d.
Honour the charge they made!
Honour the Light Brigade,
Noble six hundred!
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