I went to a conference today, and I learned some good things about which I will be writing shortly, but before I do that I wanted to share with you a couple of maps I saw at the conference, and a third I decided to put together myself to see what it would say.
The first map was put together by Noah Diffenbaugh of Purdue and his colleagues. Diffenbaugh et al ran a computer climate simulation designed to indicate which parts of the United States had the highest “climate responsiveness” — in other words, which regions would be most drastically affected by a set rise in global average temperature. The map that resulted, published in Geophysical Research Letters in 2008, is a bit ominous for those who love the Southwest:
On the map, areas where there will be greater impacts from a set increase in temperature are colored in red. There’s a great big fiery swath sticking eastward into the desert from Los Angeles, isn’t there? Looks like the southwest deserts, according to Diffenbaugh’s map, are very vulnerable to climate change, and will likely — according to his study — experience droughts and wider extremes in weather. This is not good, of course, for the many species evolved to fit the range of conditions formerly found in those deserts.
Speaking of species, there was another map shown today, this one put together by the Nature Conservancy in 2000. There are some readers here who’ll quibble with this map. It’s not very fine-grained. There are places of extensive and heightened biodiversity — some of the sort of blue spots in the Mojave, for instance — that aren’t registering here. Still, the “elevated” red areas aren’t a bad first screen of overall levels of biodiversity. Here’s the map:
It’s interesting to note that the southwest deserts that are most vulnerable to the effects of an increase in global temperature are also some of the most biodiverse landscapes in North America, and that according to a map eleven years out of date that doesn’t reflect the full biodiversity of the Mojave and Sonoran deserts.
As regular readers of this blog are all too aware, the last few years have seen a flurry of applications for large industrial-scale solar projects throughout that very southwest that is the part of the US most sensitive to climate change. That sensitivity has even been offered as a reason we have to build those plants: the “the deserts are doomed unless we fix climate change” line. But as solar energy is diffuse compared to other energy sources — a maximum of about a kilowatt per square meter — solar power by its very nature requires a large amount of land per unit of electricity generated.
Conversion of land area to human use is, of course, the main threat to biodiversity, and recent proposals by the US government would allow such development on anywhere from a thousand to 31,000 square miles of the threatened, biodiverse southwest.
It’s a double-bind posed to the deserts by those who propose solar plants: do you want to lose your biodiversity through climate change or through our efforts to fight climate change?
It is of course our habit of burning carbon that has created the whole climate change emergency, and driving home from the conference today it occurred to me that there was a third map I needed to see. What would it look like, I wondered, if I were to map the intensity of carbon emissions as a function of location across the US? I downloaded the total estimated CO2 emissions broken down by state from the EPA. They provided figures for each state running from 1990 to 2007, including all sources: residential, industry, power generation, transportation, the whole gamut. I took the totals for each state for that whole 18-year period. Just the totals by state weren’t quite what I wanted, though: the states are so diverse in size that trying to compare them just in terms of total emissions would be kind of pointless. I thought of calculating a per capita emissions for each state, but that still didn’t seem right. Since I wanted to map the intensity of emissions in different regions of the United States, I’d divide the emissions totals for each state by that state’s land area.
Doing this by state is misleading in certain ways, especially in the west. California and Texas both have huge stretches of unpopulated lands and dense urban centers, and averaging out emissions over the whole state necessarily obscures certain details. On the other hand, breaking it down by county, which has been done, can introduce false precision. Clark County in Nevada was a huge emitter of CO2 for many years, but a lot of those emissions came from a coal-fired power plant in Laughlin that sold power to Los Angeles. No matter which sieve you choose, you lose some detail you might want. Still, as an overall image of large regions’ contributions to the US’s carbon emissions, I think the map I generated is interesting, especially if you remember that West Texas and eastern California produce much less carbon dioxide than their more industrialized opposite partners. My map:
I was a little surprised that there wasn’t more nuance in the results. The glaring red in the northeast actually obscures another fractal layer of difference, with New Jersey leading the Carbon team at more than 300 kilotons of CO2 emitted per square mile. Which means the range among the red states (so to speak) is far greater than the range among all the rest. Speaking strictly numerically, it’d be more accurate to have colored the rest of the states blue.
But there it is, rather unambiguous no matter how I divide it up.
So let’s run through what these maps seem to show, in the context of the rush to solar development:
The Southwest is the most vulnerable region to the effects of climate change, and;
The landscapes threatened by that disproportionate impact are some of the most biodiverse in the country, and;
The solution we are offered is to threaten that biological diversity even more, and;
This is due to a crisis for which the other side of the country bears the burden of responsibility for creating.
Beautiful piece, Chris. Thank you.
Those eastern U.S. states are getting busy with their own “desert” that inspires dreams of renewable energy and concerns for its future: the Atlantic ocean. The Department of the Interior wants to “streamline” leasing for offhore wind farms in the Atlantic, and things are moving very fast. I don’t have a total planned GW number at my fingertips, but both state and federal waters are being eyed. In the news last week, a transmission line company filed a right of way application with the Deparment of Interior for a more than 350 mile long undersea transmission cable system. If you read this link you’ll see that this project, if built, will determine where a lot of offshore wind farms will go: http://green.blogs.nytimes.com/2011/04/01/offshore-wind-backbone-begins-to-take-shape/?partner=rss&emc=rss.
It remains to be seen whether lessons from desert solar permiting will be applied to offshore wind.
Nice maps.
And I’ll sign on to the Executive Summary at the end there.
Especially since some of them—tortoises in particular, and bighorns—are probably better adapted to the very different range of conditions that pertained there before 20,000 years ago or so.
yeah
Speaking strictly numerically, of course, your arbitrary categorization of a continuous variable and the wavelengths of light you’ve chosen to represent the categories are obviously rhetorical, not strictly numerical. (But you knew that.)
Sure.
Reminds one strongly of this map. But you knew that.
But hey, come on now, no point in pitching states and coasts against each other is there? We’re all in this together, aren’t we?
Aren’t we?
Is there?
Unfortunately, there are layers of complication that your map doesn’t capture. Electric power fungibility is a big one.
Washington State’s power demands are largely supplied by regionally-generated hydropower. The development and continued operation of that infrastructure has certainly incurred its own environmental costs. However, those probably aren’t generally captured very well by carbon emissions accounting at this point.
Washington’s governor and legislature have mandated the beginning of a transition of the sole coal-fired generating plant in the state to being fueled by something else (probably natural gas) by 2025. That plant is a merchant plant, not owned by a power utility, and sells its output on the power market.
While the impacts of hydro- and coal-fired power infrastructure have long been debated in the region, a more immediate issue in Western Washington of late has been a flurry of proposals for biomass-fueled (read wood-fired) boilers for cogeneration at paper and pulp mills, or in some cases, for direct generation of electricity. The biomass sources are almost always described as being slash and other woody debris. There are many fuzzy details around the carbon impacts of these proposals, including the adequacy of fuel supplies, sustainability of the forests if this material is removed, the carbon-neutrality of burning this material as opposed to leaving it on the forest floor to decay, impacts from the transportation of the material from forests to combustor, and who actually receives the benefit of the generated power. In the case of the mills, several are reportedly planning to use the cogen power to operate their mills while selling their excess lower-cost contracted hydropower allocations on the power market for higher rates.
Much of the market for excess power generated in Washington is in the Southwest. Thus carbon showing up in the map as generated here may effectively be for the benefit of consumers there. While there may be a reasonable argument that the Southwest is looking at bearing a burden of new generating capacity in response to the past carbon sins of industrialization in the Northeast, there’s also a case that might be made that the Northwest has been bearing the burden for the consumptive sins of the Southwest, and that our burden may be increasing in the future.