As Antarctica warms, a citadel of ice begins to melt

This is a re-post from Yale’s e360 blog by Fen Montaigne, author of the new book, Fraser’s Penguins: A Journey to the Future in Antarctica.

The fringes of the coldest continent are starting to feel the heat, with the northern Antarctic Peninsula warming faster than virtually any place on Earth. These rapidly rising temperatures represent the first breach in the enormous frozen dome that holds 90 percent of the world’s ice.

In 1978, when few researchers were paying attention to global warming, a prominent geologist at Ohio State University was already focused on the prospect of fossil fuel emissions trapping heat in the Earth’s atmosphere. His name was John H. Mercer, and when he contemplated what might be in store for the planet, his thoughts naturally gravitated to the biggest chunk of ice on Earth “” Antarctica.

“If present trends in fossil fuel consumption continue…” he wrote in Nature, “a critical level of warmth will have been passed in high southern latitudes 50 years from now, and deglaciation of West Antarctica will be imminent or in progress…  One of the warning signs that a dangerous warming trend is under way in Antarctica will be the breakup of ice shelves on both coasts of the Antarctic Peninsula, starting with the northernmost and extending gradually southward.”

Mercer’s prediction has come true, and a couple of decades before he anticipated. Since he wrote those words, eight ice shelves have fully or partially collapsed along the Antarctic Peninsula, and the northwestern Antarctic Peninsula has warmed faster than virtually any place on Earth.

The question now, as humanity pours greenhouse gases into the atmosphere at an accelerating rate, is not whether Antarctica will begin to warm in earnest, but how rapidly. The melting of Antarctica’s northernmost region “” the Antarctic Peninsula “” is already well underway, representing the first breach in an enormous citadel of cold that holds 90 percent of the world’s ice.

Much attention has rightly been paid to the precipitous warming of the Arctic, where Arctic Ocean ice is rapidly shrinking and thinning, Greenland’s large ice sheets are steadily melting, and permafrost is thawing from Alaska, to Scandinavia, to Siberia.

But none of the earth’s ice zones, or cryosphere, can compare with Antarctica, which is 1 ½ times the size of the United States “” including Alaska “” and is almost entirely covered in ice, in places to a depth of three miles. The Antarctic accumulated this unfathomable volume of ice because it is a continent surrounded by ocean “” the Southern Ocean “” which acts like a great, insulating moat around the South Pole. The Arctic, by contrast, is an ocean surrounded by continents, whose landmasses moderate the polar climate.

How cold is the Antarctic? How about -128.6 degrees F cold, which is the lowest temperature ever recorded on Earth, as measured at the Soviet Antarctic base, Vostok, on July 21, 1983. The polar plateau, where legendary explorers such as Robert Falcon Scott perished, routinely records temperatures of -70 or -80 degrees F in winter. So it will be quite some time before the heart of Antarctica’s vast ice dome begins to melt.

The periphery, however, is another matter, and steady warming there has the potential to raise global sea levels many feet and to affect global ocean circulation.

No place on the fringes of Antarctica has warmed with the swiftness of the Antarctic Peninsula, a crooked, 900-mile finger of land that juts toward the tip of South America. A 60-year temperature record on the northwestern Antarctic Peninsula, taken at a research base originally built by the British and now run by the Ukrainians, paints a stark picture: Winter temperatures have increased by 11 degrees F and annual average temperatures by 5 degrees F. Ninety percent of 244 glaciers along the western Antarctic Peninsula have retreated since 1940. Sea ice now blankets the Southern Ocean off the western Antarctic Peninsula three fewer months a year than in 1979, according to satellite data.

In addition, ice shelves “” large slabs of ice that flow off the land or out of submarine basins and float atop the ocean “” have been disintegrating up and down the peninsula. The most notable breakup occurred in early 2002, when several summers of warm weather heated up the surface of the Larsen B Ice Shelf, creating countless melt ponds that enabled warmer water to seep down into the ice shelf. That led in March 2002 to what’s known as a “catastrophic” break-up; the ice shelf, once the size of Connecticut, shattered in a matter of days.

“We are already at the point where the changes we’re seeing in this part of Antarctica are unprecedented throughout the entire period of human civilization,” said Ted Scambos, the lead scientist at the National Snow and Ice Data Center in Boulder, Colo.

The level of warming in Antarctica is far more severe than global warming of the past century, which has been about 1.4 degrees F. One major cause is that the warming of landmasses and oceans to the north has set up a sharper contrast with Antarctica’s intense cold. That has led to a strengthening of northerly winds, pulling far warmer air down from the south Pacific and south Atlantic onto the Antarctic Peninsula.

“One of the fundamental laws of thermodynamics is that heat always goes from warm to cold,” said Douglas Martinson, an oceanographer and Antarctic specialist at Columbia University’s Lamont-Doherty Earth Observatory.

The physical changes “” especially the drop in sea-ice duration “” have had major ecological effects. Ice-dependent organisms, including certain species of phytoplankton, are declining where sea ice is disappearing. The most important link in the Antarctic food chain “” ice-dependent Antarctic krill, on which just about every seabird or marine mammal in Antarctica feeds “” also appears to be in decline. (One study suggested that krill in the southwestern Atlantic sector of Antarctic waters had fallen by 80 percent, but other krill specialists think the decline is not nearly so steep.)

hot-penguin.jpgAt the top of the Antarctic food chain, Ad©lie penguins are suffering where warming is most pronounced. Not only is their winter feeding platform “” sea ice “” shrinking. But the main components of their diet “” Antarctic krill and Antarctic silverfish, both of which are ice-dependent “” are in shorter supply. As a result, Ad©lie penguin populations in the northwestern Antarctic Peninsula have plummeted by 75 percent and more. Ice-avoiding species, such as gentoo and chinstrap penguins, are moving in.

“We are seeing the creation of a new ecosystem for which there is no precedent,” said Hugh Ducklow, a phytoplankton specialist at The Ecosystems Center at the Marine Biological Laboratory in Woods Hole, Mass. and head of a major long-term climate change study along the western Antarctic Peninsula. “There is an entire, distinct ecosystem just living in and on the ice. So as sea ice begins to decline and then fails to form, as is now happening very rapidly, all these organisms that depend on the timing and the existence and extent of sea ice for their successful feeding and breeding will be high and dry. If the warming continues, we are eventually going to get to the point where sea ice won’t form anymore, and that would be catastrophic to the system.”

Not only are air temperatures rising. Changing atmospheric and oceanic circulation patterns around Antarctica have caused the deep, Antarctic

Circumpolar Current to be funneled up onto the continental shelf in western Antarctica. In winter, that water can be as warm as 37 degres F, which sounds cold, but in fact is considerably warmer than the surface water “” which hovers around 32 degrees F “” and vastly warmer than air temperatures, especially in winter. This huge volume of relatively warm water on the continental shelf is having an enormous impact, since water holds 1,000 times more heat than air.

“This Circumpolar Current water is just blisteringly hot,” said Martinson, speaking in relative terms. “The penguins down there will have to put on baggies and sunglasses!” In Martinson’s mind, rising ocean temperatures have played the key role in the warming of the Antarctic Peninsula and the melting of ice shelves, glaciers, and sea ice.

Of particular concern to scientists is the effect of this warmer water on the Pine Island and Thwaites glaciers, located at 75° South, below the Antarctic Peninsula. Robert Bindschadler, a senior fellow at the Goddard Space Flight Center and an expert on Antarctic ice, believes that the warmer waters are melting the submerged undersides of the ice shelves attached to these glaciers, causing them to grow thinner; in places, the Pine Island Ice Shelf is thinning at a rate of 160 feet a year, and the melting is effectively loosening the grip of the Pine Island Glacier on the sea floor, causing the vast river of ice behind it to accelerate into the sea. The Pine Island Glacier is now charging into the Amundsen Sea at a rate of about two miles a year.

One of Antarctica’s premier penguin researchers, David Ainley, and two colleagues recently forecast the impact on these two polar penguin species if global temperatures rise 2 degrees C “” 3.6 degrees F “” above pre-industrial levels, something that almost certainly will occur this century. They concluded that Ad©lie and emperor penguin colonies north of 70° South “” comprising half of Antarctica’s 348,000 pairs of emperor penguins and three-quarters of the continent’s 2.5 million pairs of Ad©lies “” “are in jeopardy of marked decline or disappearance, largely because of severe decreases in pack-ice coverage and, particularly for emperors, ice thickness.”

Bill Fraser, who has devoted three decades of his life to studying penguins and other seabirds on the northwestern Antarctic Peninsula, has seen populations of Ad©lie penguins in his study area fall from more than 30,000 breeding pairs in 1975 to 5,600 pairs today. He expects Ad©lies to disappear in the region in his lifetime.

“They’re on a decline,” he said, “that has no recovery.”

Fen Montaigne

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33 Responses to As Antarctica warms, a citadel of ice begins to melt

  1. Prokaryotes says:

    Maiden Indian Scientific Expedition to the South Pole
    Indian Flag Hoisted Today at the South Pole

  2. Prokaryotes says:

    Antarctic Methane Could Yield Warming Secrets

    Argentinian geologist Rodolfo del Valle has found a similar belch going on right now in Antarctica, albeit on a smaller scale. Gases bubbling up from the seafloor are turning parts of the waters off the Antarctic Peninsula into a noxious Alka-Seltzer, potentially worsening global warming and even killing local wildlife.

    The tricky thing is, no one really knows how dangerous the frozen methane ice is. We know there’s a lot of it, probably trillions of tons, locked in near-freezing temperatures of continental shelves around the world. If it all burst into the atmosphere at once, the effects on climate would be catastrophic.

  3. Prokaryotes says:

    Methane May Be Building Under Antarctic Ice Methane May Be Building Under Antarctic Ice

  4. Prokaryotes says:

    Lake Vostok is an oligotrophic extreme environment, one that is supersaturated with oxygen, with oxygen levels 50 times higher than those typically found in ordinary freshwater lakes on Earth. The sheer weight of the continental icecap sitting on top of Lake Vostok is believed to contribute to the high oxygen concentration. Besides dissolving in the water, oxygen and other gases are trapped in a type of structure called a clathrate. In clathrate structures, gases are enclosed in an icy cage and look like packed snow. These structures form at the high-pressure depths of Lake Vostok and would become unstable if brought to the surface.

    Researchers working at Vostok Station produced one of the world’s longest ice cores in 1998. A joint Russian, French, and U.S. team drilled and analyzed the core, which is 3,623 metres (11,886 ft) long. Ice samples from cores drilled close to the top of the lake have been analyzed to be as old as 420,000 years, suggesting that the lake has been sealed under the icecap for between 500,000 and more than a million years. Drilling of the core was deliberately halted roughly 100 metres (300 ft)[5] above the suspected boundary where the ice sheet and the liquid waters of the lake are thought to meet. This was to prevent contamination of the lake from the 60 ton column of freon and aviation fuel Russian scientists filled it with to prevent it from freezing over.

    From this core, specifically from ice that is thought to have formed from lake water freezing onto the base of the ice sheet, evidence has been found, in the form of microbes, to suggest that the lake water supports life. Scientists suggested that the lake could possess a unique habitat for ancient bacteria with an isolated microbial gene pool containing characteristics developed perhaps 500,000 years ago.

    In early 2010 the head of the Russian Antarctic Expedition, Valery Lukin, announced that a team of Russian scientists had only 100 meters of ice left to drill in order to reach the water. According to Lukin, new equipment had been developed by researchers at the St. Petersburg Nuclear Physics Institute that would ensure the lake remains uncontaminated upon intrusion. The scientists expect to reach the lake in 2010-2011.

  5. Prokaryotes says:

    Fossil water or paleowater is groundwater that has remained sealed in an aquifer for a long period of time. Water can rest underground in “fossil aquifers” for thousands or even millions of years. When changes in the surrounding geology seal the aquifer off from further replenishing from precipitation, the water becomes trapped within, and is known as fossil water.

    The Ogallala Aquifer and Nubian Sandstone Aquifer System are among the most notable of fossil water reserves. Fossil aquifers also exist in the Sahara, the Kalahari, and the Great Artesian Basin. A further potential store of ancient water is Lake Vostok, a subglacial lake in Antarctica.

  6. Prokaryotes says:

    * 1959 Antarctic Treaty System
    * 1964 Agreed Measures for the Conservation of Antarctic Fauna and Flora
    * 1978 Convention for the Conservation of Antarctic Seals
    * 1982 Convention for the Conservation of Antarctic Marine Living Resources
    * 1988 Convention on the Regulation of Antarctic Mineral Resource Activities
    * 1998 Protocol on Environmental Protection to the Antarctic Treaty

  7. Anne van der Bom says:

    “since water holds 1,000 times more heat than air”

    The density of air is 1.2 kg/m³, specific heat is 1 J/g/K, that gives it a specific heat of 1.2 kJ/m³/K.

    Water has a specific heat of 4.2 J/g/k and a density of 1000 kg/m³, thus stores 4.2 MJ/m³/K.

    Water stores 3500 times more heat than air, not 1000 times.

  8. I read this

    The Ferocious Summer: Palmer’s Penguins and the Warming of Antarctica by Meredith Hooper

    a couple of years back and it left me in no doubt that all those who claim that because Antarctic Sea Ice is increasing then there is no problem are very, very wrong.

  9. Pbo says:

    Summer is comming to the Arctic now.

    15.8 degrees C at Nuuk, Greenland according to DMI:

    At bit early perhaps?

  10. paulm says:

    Arctic winter moves south…. -9 here in Vancouver, Canada.

  11. Wit's End says:


  12. bratisla says:

    “One of the fundamental laws of thermodynamics is that heat always goes from warm to cold,” said Douglas Martinson, an oceanographer and Antarctic specialist at Columbia University’s ”

    If it refers to the principles of thermodynamics, it is alas incorrect – denialist do the same mistake. Heat flux can go from cold to warm, with proper tools , otherwise we couldn’t have fridges :)
    It is true, however, that the second principle implies with the first that you have to do extra efforts to create heat flux from a cold system to a warm system. So, naturally, you observe far more heat flux from warm places to cold places.

    Sorry, but since I laughed so hard when I saw denialists (and I use this term on purpose) using this argument to refute greenhouse effect itself, my personal integrity cannot let pass this “error”, even though I suspect that Dr Martison was only simplifying the question for the layman since this is the natural tendency anyway.

    In short : I just played the pedantic role :]

  13. Prokary otes says:

    Abrupt change of Antarctic moisture origin at the end of Termination II

    The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C East Antarctic ice core provide new insights on the sequence of events involved in Termination II, the transition between the penultimate glacial and interglacial periods. This termination is marked by a north–south seesaw behavior, with first a slow methane concentration rise associated with a strong Antarctic temperature warming and a slow deuterium excess rise. This first step is followed by an abrupt north Atlantic warming, an abrupt resumption of the East Asian summer monsoon, a sharp methane rise, and a CO2 overshoot, which coincide within dating uncertainties with the end of Antarctic optimum. Here, we show that this second phase is marked by a very sharp Dome C centennial deuterium excess rise, revealing abrupt reorganization of atmospheric circulation in the southern Indian Ocean sector.

  14. paulm says:
    Running the Polar Circle marathon
    After a year of training, Nick Mead tackles the Polar Circle marathon, and finds that unseasonally warm temperatures of -10C have led to some treacherous footing

  15. Prokary otes says:

    Rapid climate change: Lessons from the recent geological past

    Rapid, or abrupt, climate change is generally regarded as a change in the climate system to a new state following the crossing of a threshold. It generally occurs at a rate exceeding that of the change in the underlying cause. Episodes of rapid climate change abound in the recent geological past (defined here as the interval between the last glacial maximum, dated to approximately 20,000 years ago, and the present). Rapid climate changes are known to have occurred over time periods equal to or even less than a human lifespan: moreover, their impacts on the global system are sufficiently large to have had significant societal impacts. The potential for similar events to occur in the future provides an important impetus for investigating the nature and causes of rapid climate change. This paper provides a brief overview of rapid climate change and an introduction to this special issue, which presents results generated by the palaeoclimatic component of the UK Natural Environment Research Council’s rapid climate change programme, called RAPID. The papers in the special issue employ palaeoclimatic proxy data-sets obtained from marine, ice core and terrestrial archives to reconstruct rapid climate change during the last glacial cycle, its subsequent, termination and the ensuing Holocene interglacial; some papers also report new attempts to match the palaeoclimate data to hypothesised causes through numerical modelling. The results confirm the importance of freshwater forcing in triggering changes in Atlantic Meridional Overturning Circulation (MOC) and the close links between MOC and rapid climate change. While advancing our understanding of these linkages, the RAPID research has highlighted the need for further research in order to elucidate more specific details of the mechanisms involved.

  16. Prokary otes says:

    Atmospheric CO2 and abrupt climate change on submillennial timescales

    We present new multi-decadal CO2 records that cover Greenland stadial 9 (between Dansgaard-Oeschger (DO)
    events 8 and 9) and the abrupt cooling event at 8.2 ka. The CO2 records come from Antarctic ice cores but are
    well synchronized with Greenland ice core records using new high-resolution CH4 records,precisely defining the
    timing of CO2 change with respect to abrupt climate events in Greenland.
    Previous work showed that during stadial 9 (40~38 ka), CO2 rose by about 15~20 ppm over around 2,000 years,
    and at the same time temperatures in Antarctica increased. Dust proxies indicate a decrease in dust flux over the
    same period. With more detailed data and better age controls we now find that approximately half of the CO2
    increase during stadial 9 occurred abruptly, over the course of decades to a century

  17. Pbo says:

    Well said, End Wit!

    Sorry for my OT comment BTW. I mixed up Antarctic and Arctic. Hard to differ in such times. Ha, ha ;-)

  18. Colorado Bob says:

    Pbo –

    Hudson’s Bay – Freeze-up over 1 month late.
    Record heat in Russia
    Rain in interior Alaska
    15.8 degrees C at Nuuk, Greenland

  19. Rick DeLong says:

    “The Antarctic accumulated this unfathomable volume of ice because it is a continent surrounded by ocean — the Southern Ocean — which acts like a great, insulating moat around the South Pole. The Arctic, by contrast, is an ocean surrounded by continents, whose landmasses moderate the polar climate.”

    This explanation is just plain incorrect. Water acts as a moderating influence, not the other way around. Antarctica has accumulated this amount of ice because it is a landmass situated directly over the pole.

  20. Roger B. says:

    Colorado Bob,

    Through Nov. 22, Iqaluit, Nunnuvut has averaged 16.48 F (9.16 C) above the 1971-2000 average for November. It has had many days in the 30s F this month. Churchill has been pretty cold over the last 5 days as cold moved in from the west but it is still 7.93 F (4.41 C) above the 1971-2000 average for November.

    It has certainly been extremely warm in the Hudson Bay region this year and the bay should freeze up much later than average. The extreme warmth extends down to Sault Ste. Marie where we’ll have the highest or second highest yearly average temperature dating back to 1931.

    Roger Blanchard
    Sault Ste. Marie, MI

  21. Sasparilla says:

    With both the Arctic and the Antarctic it seems like we should be creating a genetic library of the organisms that live there (large and small, dry and wet – as well as much information as possible) before they and the environments they live in are wiped from existence by us. Mostly, I was thinking of the Antarctic krill / algae and the creatures that feed off of that (fish, seals, penguins, birds), much of the life in the Antarctic is powered by those krill. The Arctic is already gone, we have a few decades if we’re lucky there and we seem to have a little longer with the Antarctic.

    At some point, perhaps 1000 years from now, we may get ice back at the poles and it would be good to have the option to repopulate these environments that we destroyed previously. This would mean multiple copies of each organism to assure enough genetic diversity when, possibly, they are repopulated.

    In some sense, these environments are so outside of the usual human experience, its almost as if these were two small mostly ice planets that we are destroying. While this should be something done at the governmental level, good luck with that these days, it seems like this should be able to be started and funded privately (their are alot of people who know what is going on and would pay for something like this, myself included). Something we might be able maybe “save” / “preserve” to an extent.

    Joe, your website might have the visibility and authority to at least start serious discussions about such a goal – i.e. kick it out there so it could happen. Could you consider authoring an article (talk to scientists in appropriate fields) about something like this?

  22. Michael says:

    Rick DeLong (21),

    The “insulating moat” around Antarctica is due to the circumpolar winds (polar vortex); this also explains why the Antarctic Peninsula has warmed much faster than the rest of Antarctica, since it sticks outside the vortex.

    Also, speaking of the polar vortex, the one over the Arctic has just separated in half due to extremely warm air intruding into the Arctic from over Alaska and Greenland (just as it did last winter and the winter before), as shown in the 500 mb heights:

    Here is an animation of the 2009 split, which preceded record cold and major snowstorms in the U.S. and Europe (which is currently happening over the western U.S. at the moment); this shows vorticity where winds are blowing around the polar vortex (equivalent to lower heights in the link above, note the similarities):

  23. BB says:

    I’m getting confused with the above image, and the one from another CP post:

    The NASA image clearly indicates an extreme warming/cooling couplet along the Antarctic peninsula that seems to remain rather steady between the various years depicted in the image, but yet you get the appearance of constant warming across the entire Antarctic surface, with absolutely no cooling.

    Is the key-less image included above another one of those ‘designed-for-effect’ graphics that do not have to indicate their metrics? Or is the above one correct and the NASA one incorrect? If they are both correct, then it’s certainly confusing where it does not need to be.

    [JR: Yes, that graph is the key-less 50-year trendline from one of the studies I linked to. The Antarctic Peninsula’s most rapid warming has been in the last few decades.]

  24. dbmetzger says:

    Tracking Greenland’s Glaciers
    A team of scientists traveled to Greenland to track the island’s glaciers, whose flow and melt rate have sped up recently and are losing ice mass. This could lead to rising sea levels, and scientists say this must be studied for coastal planning policy.

  25. Pbo says:

    Colorado Bob@20: It is terrible – no news covarage what so ever (from a scandinavian viewpoint). Did the deniers shut down the news service entirely?

    I demand answers. This is just unacceptable!

    My standing is that warm arctic, cold continents seem to be the rule. This should be communicated. References at Artic Report Card (NOAA).

    Above summertime temperature in Greenland in November is just plain crazy.

    Media please!

  26. Inverse says:

    “One of the fundamental laws of thermodynamics is that heat always goes from warm to cold”

    Genius !! Douglas Martinson you must have stayed up all night working that one out !!!

    This is the similar but it sounds more scientific!!
    “If a body radiates more than it absorbs, it cools off”

  27. Prokary otes on Wally Broecker’s ‘The Great Ocean Conveyer’, as it happens I am working my way through that one right now and some interesting and convoluted thinking going on to be sure. Almost as tortuos as the last chapter of Richard Dawkins ‘Climbing Mount Improbable’ entitled ‘A Garden Inclosed’ about the life cycles of the wasp species that fertilise figs. Both are fascinating.

    It is such close dependencies between species that keep the ecology of this planet habitable which scientists such as Lindzen clearly fail to grasp. That a mismatch in timing between a particular insect life cycle change and of the plant on which it depends for food or shelter is so detrimental to both seems beyond their comprehension. As temperatures climb and climates are disrupted then the incidences of such ecological dislocation can only increase.

  28. MartinJB says:

    Minor correction: Scott died on the Ross Ice Shelf, not on the polar plateau. He was actually quite close to one of their base camps when he died. Close but far… the weather made travel quite impossible.

  29. The White Rabbit says:

    Nit Wit’s end reflects the current priorities of spending billions on looking for terrorists in the backyard, while ignoring the warnings of NOAA, National Weather Service, NASA and most eductational institutes that have been monitoring the effects of climate change. Even the Department of Defense (DENIX on the web) seems to acknowledge climate change and man’s influence.

  30. Archimedes says:

    Since ice floats because it is less dense than water but takes up more space than water, how can melting ice cause sea levels to rise? One major cause of rising sea levels is urban sprawl. Precipitation that used to become ground water now becomes runoff because so much of the earth’s surface is covered with buildings, concrete, asphalt, highways, etc. Precipitation to earth coverings to drains to rivers to seas.

    [JR: Antarctica is a continent. When ice melts on it, seas rise.]

  31. Archimedes says:

    Climate change I believe in. Where I live used to have a humid sub-tropical climate. As you know, the Great Lakes were formed by glaciers, so it must have been pretty cold then. But, nothing to worry about should there actually be global warming it won’t last long. The global freezing predicted in the 1970’s passed unnoticed!! Proponents of global warming claim that there are tens millions of like proponents. It is suggested that these proponents pull out all stops and fund these abatement programs themselves. One plan to prevent a considerable amount of pollution and at the same time conserve energy would be for the global warming activists to simply eliminate water heaters from their living quarters. As for the rest of us, we are still paying for and will continue to pay for Al Gore’s self-serving ethanol debacle.