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Bridging climate science, citizens, and policy


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IPCC’s Impacts, Adaptation, and Vulnerability Report Issued

The IPCC’s Fifth Assessment Report’s Working Group II (AR5 WGII) issued their report today.  I do agree with some of the opining characterizing the report as ‘alarmist’ – from the standpoint that I don’t think there is enough information presented simultaneously regarding opportunities for action.  People don’t respond well to persistent negative messages.  Would climate activists subject their children to daily messages of upcoming death, devastation, and the collapse of civilization?  If not, then why do they think adults are any better at handling the same messaging?

That said, I believe that scientists settled the science years ago.  I think it is highly unlikely scientists will identify anything fundamental to change that science in business as usual activities.  What will change is the climate’s response to activities changed by policy.  With new and updated policies, mitigation and adaptation will occur.  Therefore, I spend as much or more time on policy discussion than science discussion, using the science as my foundation.  As the picture on this blog emphasizes, I operate as a bridge between these two distinct sides of the problem.  Scientists typically don’t understand policy processes (to the point they eschew social science findings and believe physical scientists should exclusively inform and decide policy), while policymakers continue to ask for more actionable information.

What follows is a summary of high-level results (Summary for Policymakers) from this new report. I want this post to serve as something I can point to repeatedly in the future for these results.

OBSERVED IMPACTS, VULNERABILITY, AND ADAPTATION IN A COMPLEX AND CHANGING WORLD

1. In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the oceans.

2. In many regions, changing precipitation or melting snow and ice are altering hydrological systems, affecting water resources in terms of quantity and quality (medium confidence).

3. Many terrestrial, freshwater, and marine species have shifted their geographic ranges, seasonal activities, migration patterns, abundances, and species interactions in response to ongoing climate change (high confidence).

4.  Negative impacts of climate change on crop yields have been more common than positive impacts (high confidence).

5. At present the world-wide burden of human ill-health from climate change is relatively small compared with effects of other stressors and is not well quantified (small-medium confidence).

6. Differences in vulnerability and exposure arise from non-climatic factors and form multidimensional inequalities often produced by uneven development processes (very high confidence).  These differences shape differential risks from climate change.

7. Impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones, and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability (very high confidence).

8. Climate-related hazards exacerbate other stressors, often with negative outcomes for livelihoods, especially for people living in poverty (high confidence).

9. Violent conflict increases vulnerability to climate change (medium evidence).

Number 6 tells me that differential risk can be reduced by helping developing countries develop more quickly.  They will bear the early and severe brunt of climate change effects despite contributing the smallest portion of anthropogenic climate change forcing.  Despite this, most climate activists want to keep these countries in their current state by preventing them from industrializing.

Number 7 is relevant to the climate activist vs. Pielke Jr. brouhaha (which activists claim means very little to them at the same time they issue post after post and tweet after tweet regarding their personal opinion of Pielke).  The IPCC states: “For countries at all levels of development, these impacts are consistent with a significant lack of preparedness for current climate variability in some sectors” (emphasis mine).  What this tells me is human systems are vulnerable to today’s climate, which has a small fraction of human influence (read: overwhelmingly most influence is natural).  The focus then should be on preparing for today’s climate variability as primary steps toward dealing with tomorrow’s variability.  I don’t hear enough from today’s climate activists how today’s infrastructure can’t handle today’s climate variability.  Most of what I hear deals with 2050 or 2100 – dates when most of us will be dead.  Why not focus instead on today’s infrastructure, which we know are deficient?  Indeed, this is exactly what the report suggests we do.

The Summary continues with Adaptation Experience:

1. Adaptation is becoming embedded in some planning exercises, with more limited implementation of responses (high confidence).

2. Adaptation experience is accumulating across regions in the public and private sector and within communities (high confidence).  Governments at various levels are starting to develop adaptation plans and policies to integrate climate-change considerations into broader development plans.

It’s late in the <2C warming game for these adaptations to take place, but at least people are initiating them somewhere.  Municipalities and collections thereof are the hotspot for climate adaptation and mitigation plans and policies.  In the US, national policy is virtually nonexistent.  My hope is that local policies grow in scale.  We need to start evaluating plans and policies to inform additional locales as well as scale them up for larger governmental entities – how do they need to change for state and regional levels, for instance?

I’ll have more on this and related topics in the future as I continue to read through the report.


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Research: New Land Surface Warming Paper & Post

A quick word and some questions on a SkepticalScience post that discusses yet another warming analysis that comes up with the same answer than other studies have.   The post itself is good if you want a paper summary.  Where I think it needs attention is the “so what” part.  I’ll start with the concluding paragraph because it is what triggered a desire to actually write something about the post instead of walking away from it.

How much more evidence do we need?  The accuracy of the instrumental global surface temperature record is essentially settled science at this point.  The Earth is warming, it’s warming very fast, and continuing to deny this fact is a waste of time.

Many researchers and activists won’t like my answer: we don’t need much more scientific evidence.  Indeed, I would argue that the science largely weighed in years ago and additional information has only provided small-scale refocusing on parts of the issue.  Scientists haven’t discovered anything truly transformative in many years.  Are fields advancing as a result of new observations, methodologies, and expertise.  Yes, but that doesn’t answer Dana’s question.  What climate field advancement will be the one that magically triggers a switch in skeptics’ minds?  What new data set or analysis technique will do the trick?  I argue that no such advancement will ever occur.  Do we really believe that nobody has yet been smart enough to develop the one advancement that unlocks universal understanding of a complex topic?  That’s clearly an absurd assumption, but it seems to permeate this and other similar posts.  The spectrum of people who care about this topic have made up their minds (whether through tribalism or critical thought).  I will not convince any large number of skeptics to accept my argument any more than Hansen, Gore, or McKibben.  And here is where things get raw: strategies that those activists and most others have employed will not convince those people who don’t care about this topic.  As voices get more shrill and combative, more people tune the arguers out.

So if the evidence isn’t the problem, what is?  I believe the problem is the use of climate science as a proxy for a values fight.  Most people are unwilling to identify and fight about their values; it is much easier to throw climate science in the middle of the ring to fight for them.  Skeptics challenge the “facts” because of their beliefs and value system.  Advocates challenge the skeptics because of their beliefs and value system, not because of the “facts”.  Both groups try to bludgeon each other with “facts” and in so doing talk past each other, not to each other.  What concerns do skeptics have regarding climate change; how can advocates listen and address those concerns and vice versa.  Bypassing others’ concerns is the thing that wastes time.  So why do advocates and skeptics do it so much?


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Research: Volcanic Aerosols Largely Responsible for Recent Warming Slowdown

Climate change skeptics used the recent slowdown in observed surface warming to claim that 20th century warming was temporary and that the Earth would return to lower average annual temperatures.  They offered up many potential explanations for the slowdown, none of which make physical sense.  The Sun’s 11-year cycle (often used to explain away warming), a primary argument brought forth, is not the reason: this cycle’s solar maximum is near at hand, yet warming has slowed down recently.

Recently accepted research points to a viable physical explanation.  In addition to oceanic transport of heat to the deep ocean and recent La Nina events, sulfuric emissions from small and mid-sized volcanoes entered the lower stratosphere and reflected more incoming solar radiation than normal.  This research separated the effect of natural sulfur emissions from anthropogenic emissions, using a model, to determine the former had a much larger influence than thought.  Aerosol optical depth (AOD) is a calculated metric used to represent how opaque or transparent the atmosphere is to different radiation wavelengths.  The layer between 20 and 30 km increased 4-10% per year since 2000, which is a significant change from normal conditions – significant enough to have effects on Earth’s climate.

Here is one of the paper’s graphical results:

 photo AerosolOpticalDepth525nm-Neelyetal2013_zps8ba54484.png

Figure 1. Observed and modeled time series of stratospheric AOD from three latitude bands.  Satellite observations are represented by the black line.  Base-line model runs are in green. Model runs with the increase in anthropogenic emissions from China and India are in blue. The dashed blue line depicts a model run with 10x the actual increase in anthropogenic emissions. The model run with volcanic emissions is in red. The black diamonds and initials along the bottom of the plot represent the volcanic eruptions that were included in the model run. (Source: Neely paper; subs. req’d.)

As the caption says, satellite measurements are denoted by the thick black curve.  Note the large increase in AOD (higher opacity) over the tropics in the mid-2000s (b) and the large AOD increase over the northern mid-latitudes in the late-2000s (a).  While not a perfect fit to the observations, the model run with volcanic eruptions (red curve) does the best job of explaining the origin of the SO2.  Individual eruptions are indicated by black diamonds on the bottom of each sub-plot.  The effects of volcanic eruptions on climate are, in a general sense, well-known.  Injections of SO2 into the stratosphere reflects sunlight, which reduces the amount of energy entering the Earth’s climate system.  The difference between one large-scale eruption (e.g. Pinatubo in 1991) or many mid-sized eruptions in a short time-period (see above) is not large as far as the climate is concerned.

This could be good news as far as the climate is concerned, at least in the shorth-term.  If incoming energy were reflected back into space instead of being stored in the system, we can physically explain the observed temperature trend slowdown (see Figure 2) and treat the slowdown as real instead of waiting for that energy to transfer from the oceans to the atmosphere, for example.

There is also bad news however.  From the study (emphasis mine):

The significant portion of the radiative forcing due to increases in stratospheric aerosol from 2000 to 2010, interpreted as a mechanism of global cooling [Solomon et al., 2011], may now be completely attributed to volcanic sources and should not be considered a trend. Rather, the stratospheric aerosol layer should be treated as a natural source of radiative forcing that is continuously perturbed by volcanic injections of a range of sizes, and potentially other sources such as large fires.

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Figure 2. Global mean surface temperature anomaly maps and 12-month running mean time series through January 2013 from NASA.

We can see from the 12-month running mean time series (lower-right in Figure 2) that NASA’s temperature index increased more slowly during the latter part of the 2000s than the 1990s.  Neely et al. suggest that there is no physical reason to conclude that slowdown is a trend of opposite sign than that seen throughout the 20th century.  In other words, once the SO2 precipitates from the stratosphere, as it eventually will, the background warming trend will re-establish itself.  Indeed, future warming will likely be stronger than past warming because CO2 concentrations have not decreased in the past ten years.  To the contrary, they have increased at a faster rate than before.  Greenhouse gases have simply had less incoming radiation to absorb than they did 10 years ago due to the recent presence of SO2 in the stratosphere.

Neely’s coauthor Brian Toon had this to say:

Toon of CU-Boulder’s Department of Atmospheric and Oceanic Sciences. “But overall these eruptions are not going to counter the greenhouse effect. Emissions of volcanic gases go up and down, helping to cool or heat the planet, while greenhouse gas emissions from human activity just continue to go up.”

This situation provides a good example of another aspect of climate policy.  I wrote about geoengineering earlier this year as part of a Polar Sea Ice post (much more discussion took place here).  One proposed mechanism to reduce the impacts of climate change is human injection of SO2 into the stratosphere, which would mimic natural volcanic effects.  If we implemented such a strategy without simultaneously reducing atmospheric greenhouse gas concentrations, then abruptly stopped the injection (due to lack of funds or international controversy), the resulting warming signal would be higher post-injection than pre-injection.  The result would be unprecedented due to the large warming signal such a halt would introduce to the climate system.

In one more respect then, policymakers have wasted the past decade.  Instead of developing and implementing climate mitigation policies, international inaction continued.  Once the atmosphere removes the SO2, the climate signal will be stronger than before.  We cannot and should not rely on future volcanic SO2 emissions to mitigate our GHG emissions.  The lack of robust policies is a choice, but it is not a wise long-term choice.


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Research: West Antarctic Warming Greater Than Thought

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:

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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.

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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.


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CO2 Emissions Continue to Track At Top of IPCC Range

A new Nature Climate Change editorial (subs. req.) has a very useful graph (2 variants) that I have been looking for:

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Note first the y-axis: global CO2-emissions in Petagrams of carbon per year.  This unit is different from the other common unit used: CO2 concentrations.  The emissions eventually lead to the concentrations.  This is only the CO2 emissions, not CO2-equivalent, which might be a better variable but introduces more complexity in analysis.

Let’s go through the lines on the graph before we discuss them.  The “IS92″ lines (a-f; light blue dashed) were the emission scenarios developed for the 1992 Supplementary Report to the IPCC Assessment.  There are 40 SRES scenarios shown (thin green lines) and 6 illustrative scenarios (thick green dashed lines) that the IPCC developed for the 4th Assessment Report (AR4).  These are the scenarios most people discuss: A1B, B2, etc.  For the upcoming AR5, CO2 emissions form the basis of the scenarios.  There are ways to convert from one to the other, which is how all of these different scenarios can be plotted together.  The AR5 scenarios are labeled according to the anomalous forcing value expected in the year 2100 and a “Representative Concentration Pathway”.  Thus, RCP3 represents 3 W/m^2 forcing due to CO2 concentrations.  You can see what has to happen to global emissions to achieve this relatively low forcing value by the end of the century.  Alternatively, there is an RCP4.5, RCP6, and RCP8.5 pathway.  As a side note, my work will likely utilize the RCP8.5 pathway because we will most likely continue to move down this pathway for the foreseeable future.

Historical emissions are the black dots/line.  The estimate for 2012 emissions is the red dot.  It is obvious to see that our historical emissions has tracked near the top of any set of emissions scenarios (IS92-E, IS92-F, A1FI, A2, and A1B) and not the middle or bottom.  That has implications in climate policy because most scientific studies performed to date have focused on the low to moderate scenarios.  The reason is simple: most climate scientists thought there would be no chance of inaction once people saw what was likely to happen using even low or moderate emission scenarios.  In general, scientists were wrong.  The world has continued to increase the amount of CO2 emitted into the atmosphere, with “average annual growth rates of 1.9% per year in the 1980s, 1.0% per year in the 1990s, and 3.1% per year since 2000,” as I’ve covered in 2011 and earlier in 2012.  The post-2000 increase is largely due to China and India.

The lead author of the report posted different form of this graph and included yet another call to action that the world will ignore:

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A quick note: the RCP3 scenario’s absurdity becomes more clear post-2060: emissions have to turn negative to achieve 3 W/m^2 by 2100!  Is anyone aware of technologies that remove emissions from the atmosphere in excess of what we emit to the atmosphere?  Put another way, emissions would have to decrease to near-zero in addition to deployment of removal infrastructure.  I obviously wasn’t involved scenario development, but it strikes me as incredibly myopic to include this pathway in climate scenarios: it exists only as a fantasy, especially when you realize that important feedback processes are still not understood well enough to include them in modeling efforts.

The main point of this graph is valid though: on our current emissions trajectory, global warming of 4–6.1 °C is likely.  Given recent studies showing more sensitivity to temperature changes one order of magnitude less than this that has already started to generate real-world changes, no one can say with certainty what a 4°C rise in global temperature above the pre-industrial average will cause.

Now, I must make a very important point here.  This does not mean the end of civilization or the world.  Our species is remarkably adaptive to a wide range of conditions.  While our species has never lived in a world that warm, we have enormous advantages over our ancestors: technology.  The world might not look like it does today, and we will of course not live in the same way, but I firmly believe that whatever changes we make will allow the great majority of us to continue to live.

That is not to say that we should do nothing at all.  I have made quite clear that the current approach (UNFCCC & IPCC) has proven itself to not work.  I do not know exactly what the correct approach will be, but I think remaining in a failed paradigm is a bad idea moving forward.  We must make new efforts – the more the merrier in the short-term so we can evaluate what does and does not work.  My line of thought has developed to this: I think groups must initiate smaller efforts, and indeed I think in some cases they already have.  Regional cohesive groups generally know better what works for them and why.  A good place to start on a larger scale would be to work to understand why certain actions work in some places better than others and put policies in place to exploit those opportunities.

But 2°C is not achievable by any means that I can see.  Neither is 350ppm CO2 concentration.  Scientists and activists alike should cast aside these hard to understand numbers.  A focus on other goals: energy portfolios, land use, and adaptation plans make more sense (different numbers since we tend to operate that way).


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Antarctic Ice Shelves Melting Due To Deep Warm Ocean Water

Until just a few years ago, scientists were unsure why the global energy budget seemed to indicate that an enormous amount of energy couldn’t be accounted for.  Incoming and outgoing radiation is fairly straightforward to measure and a simple energy budget is easy to calculate.  Accounting for all of the movement of energy within Earth’s climate system imposes a great deal of complexity into the process.  Still, numerous attempts were made to try to track down what was growing into a very large amount of energy: was it erroneous measurements or calculations, or did we remain woefully ignorant of significant physical processes?

Then in 2009, two major papers were published that closed the majority of the unaccounted for energy in the climate system.  The excess energy was being stored as heat in the ocean, specifically the deep ocean.    The volume of the Earth’s oceans is estimated to be 1.332×109 km3.  That is obviously a very large volume within which energy can be stored.  What has happened over the course of the past century or so is warmer and warmer water has been forced down to the bottom of the world’s oceans.  Usually, warm water rises, but the water in question is just above the freezing point of fresh water.  At those temperatures, salinity has an increased role in controlling density.  Water sinks when sea ice forms because sea ice is made up of only pure water, leaving excess salt in the remaining ocean water.  As the salinity increases, the density also increases.  Water with higher density than what is surrounding it sinks and then is transported by ocean currents around the world.

It might surprise you to learn that ocean currents can take decades to centuries to complete one cycle around the entire globe.  That means that water that was warmed decades ago is now coming back to the places where it originally picked up that warmth.  In this case, water is upwelling off the Antarctic peninsula and it is having a very real physical effect on the region.  While localized now, that effect will soon cause additional effects across the globe.

One of the 2009 studies had this graph, showing where the excess energy was being stored:

Total Earth Heat Content from 1950 to 2003 (Murphy 2009).

This graph is troubling for a number of reasons.  One of the first things to notice is the land and atmosphere haven’t warmed up all that much, since 1950, compared to the ocean.  Next, it should be startlingly clear that a great deal of energy wasn’t being properly accounted. Third, if the ocean really is holding all this heat, shouldn’t someone have noticed before last year?  Indeed, a number of scientists speculated that the sea level rise recorded in the past 100 years was likely due to this phenomenon occurring.  Scientists being the careful people they are didn’t make pronouncements that they knew this was going on because … they didn’t have empirical proof of it.

By now, I hope a couple of things I’ve written about in this piece are starting to come together.  The ocean upwelling off the coast of Antarctica is carrying some of the energy it absorbed decades ago.  The heat anomaly of the ocean has only increased since then.  What might this mean in the future?  Well, let’s start answering that by looking at what this means in the present.  Here is a graphic put together by Douglas Martinson, a polar scientist at the Lamont-Doherty Earth Observatory who gave a talk at this year’s American Geophysical Union meeting.

Antarctic Ocean Heat

The warm upwelled water is being transported around the Antarctic continent by the Antarctic Circumpolar Current, as you can see on the right side of the graphic.  Over the past 18 years, Martinson and his colleagues have measured the physical properties of the ocean around Antarctica and came to the startling conclusion that the majority of the heat anomalies they have measured have occurred since 1960.  Unfortunately, those anomalies have been growing exponentially ever since.  While the rise was tiny at first, exponential growth for 50 years means that now ocean water is a few degrees above freezing.  This warm water is coming up and running into ice sheets that are slowly being discharged from the Antarctic interior.  Not only do the ice sheets have to contend with anomalously warm air temperatures from above, they also are facing warm water temperatures from below.  And since water holds much more energy than air per unit volume, the warmer waters rising from the ocean depths will have a much greater impact, much sooner, on the ice sheets than the warmer air will.

Okay, so what about the future?

As for how fast the ice will melt and in what locations, that depends largely on whether the upwelling warm water comes in contact with the thick ice shelf that crowds the coast and holds the block the glaciers from reaching the sea.

That, in turn, depends on the winds which drive away the surface waters and make it possible for the deeper waters to rise to the surface, said senior researcher Robert Bindschadler of NASA’s Goddard Earth Science and Technology Center and the University of Maryland-Baltimore County.

Now that the upwelling deep sea water is the clear cause of the melting ice shelf, rather than summer melt water, as had been thought in the past, it’s a question of how winds will change in a warming world and whether they will drive more warm water into the ice shelves.

For a short while longer, large-scale effects will remain muted.  Warmer waters will likely attack the ice shelves, but since the shelves’ ends are already floating in the ocean, this won’t affect global sea levels.  If the ice shelves are melted all the way back to their grounding zones on the Antarctic continent, then larger problems are at hand.  If the land-based ice sheets flow toward the ocean faster and faster, and if they come into contact with warmer ocean water, their melting will cause much faster global sea level rise.

As far as the 21st century is concerned, the West Antarctic Ice Sheet (WAIS) is less stable than the Greenland ice sheet.  Why?  Because its grounding line is actually below sea level.  Imagine if the U.S. gulf coast was much colder than it is today, cold enough for ice sheets to be piled up on it.  The WAIS is like a hypothetical ice sheet sitting on the New Orleans area.  The real-world difference is the WAIS rests on bedrock that is an amazing 2km below sea level!  That bedrock is further below sea level than Denver, CO is above it.  If warm water ever gets to this area, a vicious cycle will begin.  That cycle wouldn’t stop until most or all of the WAIS melted, which could raise global sea levels by 10ft.  Moreover, the bedrock also slopes downward inland.

Now I want to tie a number of points raised all together.  The WAIS is an unstable ice sheet.  Outflow ice shelves extend into the oceans of the Southern Hemisphere.  Water is rising from the bottom of those oceans that is warmer than the water already there.  If predominant wind currents cause additional warm water to rise faster, the ice shelves floating in the oceans will melt from below.  They will melt faster than climate model projections made over the past 20 years have indicated because of the relative lack of understanding of polar weather and climate.

I want to ask you to recall the first graph in this post, the one that shows an increasing amount of heat energy that has been stored in the world’s oceans since 1950.  All that anomalous warmth hasn’t had a chance to be transported to the Antarctic yet.  Therein lies the scary part to this: Antarctica faces decades of increasingly warm waters rising off its shores.  That would be true if we stopped all of our greenhouse forcing tomorrow.  We won’t, of course, which means the Antarctic ice sheets face more and more of a threat every year.  The world at the end of the 21st century will look quite different than it did at the end of the 20th.  How different is up to us.

h/t ClimateProgress.

Cross-posted at SquareState.


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21st Century Sea-Level Rise: More Than IPCC 4AR Projected

New research was published a few months ago that provides additional evidence that sea-level projections made by the IPCC’s 4th Assessment Report are likely too conservative: sea-levels are more likely to be 1 meter higher than they were in 1990 (Vermeer and Rahmstorf), rather than only 0.5m higher, as projected by the IPCCs multi-model ensembles.

There was nothing inherently bad about the IPCC’s 4AR; I and others simply feel that their final report had to include more conservative estimates and projections in order for world governments to sign off on its language.  That does the world’s citizens an injustice, however.  In order to correctly assess risk, people need best- and worst-case scenarios available to them.  The most likely amount of sea-level rise by 2100 provided by the 4AR came out to between 0.2m and 0.6m.  Those estimates have implications to world societies, conservative though they were.  Additional implications will enter into our lives if there is 0.4-0.8m additional rise.

I want to stay on the IPCC projections for another moment.  The 2007 estimates included rates of sea level rise between 1980 to 1999 and 2090 to 2099 in metes and mm/yr.  The mm/yr rates in particular interest me because they allow for both the IPCC projections and the updated projections from the Vermeer and Rahmstorf paper to be placed in context with actual observations.  The six emissions scenarios examined by the IPCC had rates of 1.5, 2.1, 2.1, 1.7, 3.0 and 3.0mm/yr.  Satellite observations indicate that there has been approximately a +3.2mm/yr change in sea level (linear fit since 1993).  Only two IPCC emissions scenarios are close to the observed rate, and both of them underestimate them, albeit very slightly.  It is worth pointing out that the IPCC wrote:

The global average sea level rose at an average rate of 1.8 [1.3 to 2.3] mm per year over 1961-2003.

Averages over longer periods of time like this will, by nature of the averaging, tend to reduce extreme values that are small in number, as in the case of sea-level rise in the past 10 years or so.

Onto the new research findings.  Vermeer and Rahmstorf developed and tested an updated methodology to project future sea levels based on projected changes in temperature that was originally presented by Rahmstorf in a separate paper.  The original technique was based on the assumption that the sea level response time scale was long compared to the time scale of interest.  The updated technique allows for some sea level components to change quickly to a given temperature change.  The updated technique is shown to agree very well with historical data (82% of sea-level rate variance from the year 1000 to 2000).

Applying the technique to future conditions provides another potential case against which real-world observations can be compared.  By the year 2100, three different IPCC emissions scenarios generate a range of sea level projections: 1.0m, 1.2m and 1.4m, as the figure below (from the paper) shows.  That’s a big difference between the AR4 projections, using the same emissions scenarios, of 0.2-0.4m.  That extra potential meter of sea level rise will indeed have large implications across the world.

The figure shows the possible range of sea level rise values for 3 emissions scenarios considered by the IPCC: B1 in green, A2 in blue and A1F1 in yellow.  The observed emissions to date is represented by the red curve.  One important detail to note is our actual emissions rate is currently at the high end of all those considered by the IPCC (Copenhagen Diagnosis Figure 1, after Le Quere et al. 2009).

The IPCC projected a higher future rate of sea-level rise than was observed from 1961-2003.  1.8mm/yr equals 0.18m after a century (by linear extrapolation), slightly below the 0.2 minimum projected by all emissions scenarios.  Recent observations of 3.2mm/yr equals 0.32m after a century – well within the IPCC range, but well below the Vermeer and Rahmstorf range.  So what will it take to get 1.0-1.4m of sea level rise by 2100?  10mm-14mm/yr or 3-4X as much per year as is currently being observed.  There are some important details involved with that projection.  First of all, sea level change is not linear.  It varies year to year and decade to decade.  There has to be a transition from today’s 3.2mm/yr to the 10mm/yr necessary to achieve 1m sea level rise by 2100.  The rate of sea level rise would therefore have to increase over time.

Given the state of today’s atmosphere, oceans and cryosphere, a drastic change would have to occur for sea levels to rise by 10mm+ per year by the end of this century.  It is widely known that the IPCC’s science basis did not include a number of processes and feedbacks to the globes’ continental ice sheets, glaciers and sea ice (cryosphere).  Again, that wasn’t their fault – it just happens to be a weak link in the climate community’s research.  Work has been conducted since the IPCC 4AR to rectify those shortcomings.  Much more work will have to be done in the future.  Once that area is fleshed out further, I expect the IPCC’s projections to be more closely aligned with the leading research of today.

h/t RealClimate


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Climate Scientists Regain Access to CIA Imagery

Among the hundreds of anti-science actions the Bush “administration” took in the last decade was one to prevent climate scientists from accessing declassified data from the CIA and other federal intelligence sources.  There was no threat to our national security by the data sharing agreement.  There was, however, a threat to the Cons’ War on Science.  If U.S. climate scientists were denied access to data, especially satellite data, it would be much harder for them to gain the understanding of phenomena such as ice dynamics at the poles.  It has been well documented that the poles are experiencing more effects from climate change thus far than any other part of the globe.  Unfortunately, the poles are also the hardest for scientists to access.  There are no permanent surface stations on the Arctic ice, for instance.  Antarctica is very poorly sampled.  These facts lead to the situation where globally averaged temperatures over the past 30 years are likely too low because of the sub-sampling of regions which have experienced the most warming.

The Obama administration is demonstrating that it is more tuned into what science can offer society: the CIA is again sharing data with climate scientists.

The data not only helps out climate scientists, but their work in turn helps out the CIA and other agencies charged with protecting our national security.  As I’ve written before, only fools and ideologues believe that desertification of arable land, rapidly rising sea levels, ocean acidification and mass migration of climate refugees aren’t threats to nations across the globe.  By trying to bury the problem, the Bushies added additional threats to our country.  Cons such as Sens. Inhofe and Barrasso (from two of CO’s neighboring states) fear conspiracy theories more than the real events of our day.

The program resurrects a scientific group that from 1992 to 2001 advised the federal government on environmental surveillance. Known as Medea, for Measurements of Earth Data for Environmental Analysis, the group sought to discover if intelligence archives and assets could shed light on issues of environmental stewardship.

In a positive sign that scientists aren’t beholden to a rigid ideology, the resurrection of the program includes a review of past efforts in order to determine which ones should be expanded and what additional needs exist today that need filling.

Scientists and policy makers have a lot to do to make up for the time lost during the dark years under the Bushites.  This is another step in the correct direction.


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NASA’s Orbiting Carbon Observatory Crashes During Launch

I was excited the other day to hear that NASA’s Orbiting Carbon Observatory was set for launch today.  It was designed to map carbon sources and sinks over a period of time (the carbon cycle) to assist climate scientists’ efforts to ascertain the state of our climate.  Most unfortunately, the satellite failed to reach orbit this morning after a shroud failed to separate during ascent.  Likely weighing too much, the satellite came back to Earth near Antarctica.

NASA will of course investigate the data from launch in an attempt to determine cause.  It’s too early to tell what future plans regarding similar efforts might be.  To my knowledge, I don’t think NASA or climate researchers have an operating satellite that can do what OCO was designed for.  It took eight years to plan and build this satellite, so any future replacement wouldn’t be ready for quite some time.

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