This graphic says it all:
A new article in Nature Geoscience, Central West Antarctica among the most rapidly warming regions on Earth (subs. req’d), presents up-to-date information on conditions of the West Antarctic Ice Sheet (WAIS). The most common theme of climate science is present within this story: warming is occurring faster than scientists thought it was or projected just a few short years ago. This study compares its results against similar efforts and confirms some of the fears of the cryosphere. Large portions of both the Arctic and Antarctic are among the spots warming the fastest on Earth. What does this mean? It means accelerating sea level rise, influxes of fresh water into the world’s oceans, and rapidly changing ecosystems. It means there are likely other effects of anthropogenic global warming occurring across the globe, but because our observation networks are sparse, we’re just not aware of them yet.
Two important figures from the paper:
Figure 1. Color shadings show the correlation between the annual mean temperatures at Byrd and the annual mean temperatures at every other grid point in Antarctica, computed using ERA-Interim 2-meter temperature time series from 1979 to 2011. The star symbol denotes the location of Byrd Station. The black circles denote the locations of permanent research stations with long-term temperature records.
The warming observed at Byrd Station is, by incorporating ERA-Interim reanalysis data, also exists across a significant portion of West Antarctica. This development’s significance is this: the WAIS rests on bedrock and is grounded below sea level. As the WAIS melts, the meltwater runs to the ocean from the land, raising sea levels. If sea level around Antarctica rises high enough, the bottom of the WAIS will be exposed to water, which will hasten its melt.
Figure 2. Annual mean surface temperature change (trend×number of years) during 1958–2009 from the Byrd record (red and black circle) and from the CRUTEM4 data set (rest of map).
Figure 2 puts the Byrd warming into global context. There are areas in the Arctic and now the Antarctic that have observed +2.4°C warming from 1958 through 2009. The long time period is representative for climate and the non-zero warming represents change. On a localized scale (WAIS), the warming observed at Byrd and likely at nearby locations probably counteracted the cooling resulting from increased circumpolar westerlies. Those westerlies, as I’ve written about in my State of the Poles posts, were themselves the result of cooling in the Antarctic stratosphere as ozone depletion occurred. In essence, the strong winds blowing across lines of longitude near Antarctica largely prevented warm air at higher latitudes from being blown across the continent. The Byrd warming therefore presents an interesting case where this phenomenon isn’t the only one that occurs.
As the Montreal Protocol continues to reduce the amount of ozone-depleting substances in the stratosphere and the ozone layer replenishes itself, the anomalous westerlies will likely subside. As additional warm air is advected over Antarctica, the continent will experience fuller effects of global warming. In turn, the rest of the planet will experience the results of those effects. This is an example of one science policy working while another science policy remains mostly flatlined. The 2012 18th Conference of Parties continued to demonstrate that the same framework that allowed for the Montreal Protocol to be negotiated and successfully implemented has not and will not allow for a climate protocol. Decades have passed while negotiators have tried time and again to do the same thing over and over. A new approach is required. Local, bottom-up efforts need to be expanded and stoked. Someone somewhere has a much more effective set of solutions. Heck, a bunch of someones somewheres have solution sets. They need to be incubated and allowed to develop. We need to take control of those strategies and processes.
If the results of the study I’m discussing are robust, and not just true, many more climate change effects will become apparent sooner than many think. It has been known for a number of years that the West Antarctic Ice Sheet (WAIS) has, on net, lost ice mass since ~2005. This phenomenon has occurred concurrently with the Greenland ice sheet also losing mass over a similar time period. That mass loss has contributed to a, until now, relatively small amount of sea level rise.
A new study suggests that sea level rise scenarios may need serious revision quickly: the East Antarctic Ice Sheet (EAIS) has, according to NASA’s GRACE satellite data, also lost mass in the 2005-present time period. Why is this a potential big deal? Because east Antarctica contains enough water to raise sea levels by 50-60m (160-200 feet!) if they melted completely. In contrast, the water in the WAIS and Greenland amount to “only” 6-7m (~20 feet) each if they melted completely. So the EAIS contains an order of magnitude more water than the other two large ice sheets on Earth.
Here are some of the climate-related news stories that I’ve seen this week:
A new study proposes that if the West Antarctic ice sheets melted, global sea level rise would only be 10 feet, not 20 as previously estimated by other studies. The new study’s author claims that enough of the ice sheet would remain grounded on the Antarctic continent so that only some of the melting ice would find its way directly to the world’s oceans. If true, this would be at least some good news in the sea level rise arena. One take-away message is that we still don’t know nearly enough about ice sheet and glacier dynamics to reliably forecast their future conditions. These are interesting results – since they challenge previous findings, they need to be explored further.
Though not my chief concern over fossil fuel usage, a group of retired military officers argue in a recently released report that energy security and efforts to reduce the risks of climate change should be included in the nation’s national security and military planning. From the article:
The concerns extend beyond America’s dependence on foreign oil, the report says, because no matter what the source, America’s dependence on oil “undermines economic stability, which is critical to national security.”
Also, the report called for modernizing the nation’s electric power system. The country’s “fragile domestic electricity grid makes our domestic military installations and their critical infrastructure unnecessarily vulnerable to incident, whether deliberate or accidental,” said the report.
The report raised alarm about three converging concerns: A future global oil market shaped by limited supplies and increasing demand, rising fossil fuel prices caused by regulating climate-changing emissions, and the impacts of climate change on global insecurity.
Another casualty of the 2008-09 recession? CO2 emissions. Many people were curious how the worst recession since the Great Depression would impact emission trends. Energy-related carbon dioxide emissions declined by 2.8 percent last year compared to 2007. The Energy Information Administration attributed the decline to a 2.2 percent drop in energy consumption, largely because of high gasoline and diesel prices last summer and the sharp economic decline in the last half of the year. It’s not the way anybody wanted emissions to be reduced – millions of Americans are unemployed and our economy is in tatters. Meanwhile, Cons and ConservaDems watered the Waxman-Markey cap-and-trade legislation down significantly, as I’ll cover later.
As the science over the cause of climate change has become increasingly solidified, many researchers are expanding their examination of the effects of climate change. Among other examples, some recent items of note include:
North American bird species are wintering further north. An Audubon Society study conclusively shows that hundreds of species of birds are spending winters further north in recent winters than they did 40 years ago. Climate change has affected northern latitudes more than the mid-latitudes and tropics: they’ve grown warmer faster than any other region. Migratory birds’ wintering patterns have been shifted.
Sea-Level Fingerprint of West Antarctic Collapse. An important study that came out in last Friday’s issue of Science looks more closely at how sea levels around the world would be impacted if the West Antarctic Ice Sheet (WAIS) collapsed. Contrary to the incomplete assessment that was part of the 2007 IPCC Report, sea level rise won’t be equitable across the globe. Due to gravitational effects and uplift as ice mass disappears from land surfaces, oceans bordering North America and in the Indian Ocean could rise ~30% higher than previously assumed. For instance, the IPCC forecasted a 5m sea level rise for areas near Washington, D.C. The new assessment indicates a sea level rise of 6.3m (1.3m more) due to additional effects.
Okay, I’m going to bring up a couple of short-comings of this study, one of which the authors identified. This assessment did not take into account the Greenland, East Antarctic or mountain ice sheets. Anything that causes the collapse of the WAIS will undoubtedly also cause collapses elsewhere across the globe. Thus, that 6.3m sea level rise for Washington, D.C. could easily go much, much higher. The authors acknowledge that serious concerns about the impact on coastal communities is increased as a result of this study, not decreased. Second, the authors compare their assessment to the IPCC’s. As I’ve written before, recent observations from across the planet indicate that every model used in the 2007 IPCC Report underestimated recent climate change. The poles are warming faster than any model used indicated. Climate zones are shifting faster. Drought areas are expanding further. Birds’ wintering areas are shifting north sooner. CO2 concentrations are higher and positive feedback mechanisms have been initiated. This doesn’t mean the results of this Science paper are invalid, only that the specific sea level rise number used for contrast is already out of date. Policy makers must be made aware of the most recent valid research, like this paper. The challenge facing researchers is being able to provide robust, comprehensive assessments so that strong policies can be created.
Weeds will appear in new areas and disappear in others. Land managers could have a short period of time to reintroduce native plants in areas that have been taken over by invasive species. The biggest question is where will precipitation fall most often.
Hurricanes’ roles in influencing Northern Hemispheric winters are being explored. The view that hurricanes are important in maintaining the balances the atmosphere works toward in much the same fashion as mid-latitude cyclones (think of the low pressure systems that typically move west to east) has gained traction in recent years. This article describes another effort at working to determine how that mechanism compares to mechanisms like El Nino.