Friday, August 23, 2013

It's Gettin' Hot In Here!

By Jeff Simpson

The Intergovernmental Panel on Climate Change's 2013 Summary for Policymakers report was recently leaked, and many in the media are reporting the conclusion:

It is now "extremely likely"—or, 95 percent certain—that humans are behind much of the global warming seen over the last six decades.

H/T Mother Jones for digging deeper and finding the top 5 Holy Sh*T moments in the report:

We're on course to change the planet in a way "unprecedented in hundreds to thousands of years." This is a general statement in the draft report about the consequences of continued greenhouse gas emissions "at or above current rates." Unprecedented changes will sweep across planetary systems, ranging from sea level to the acidification of the ocean.
Ocean acidification is "virtually certain" to increase. Under all report scenarios, the acidification of the world's oceans will increase—the draft report calls this outcome "virtually certain." As we have previously reported, more acidity "threatens the survival of entire ecosystems from phytoplankton to coral reefs, and from Antarctic systems reliant on sea urchins to many human food webs dependent on everything from oysters to salmon."

Long-term, sea level rise could be 5 to 10 meters. Journalists are already citing the draft report's prediction that by the year 2100, we could see as much as three feet of sea level rise. But there is also a more long-range sea level scenario alluded to in the draft report, and it's far more dramatic and alarming.

Taking a look at the planet's distant past, the document ascribes "very high confidence" to the idea that sea levels were "at least 5 [meters] higher" during the last interglacial period, some 129,000 to 116,000 years ago. It also adds that sea level during this period probably did not exceed 10 meters higher than present levels. Finally, the draft report says, with "medium confidence," that temperatures at that time weren't more than 2 degrees Celsius warmer than "pre-industrial" levels.

Add it all up, and what that means is that if we exceed 2 degrees of warming beyond pre-industrial levels, then we could be looking at radically higher oceans, and submerged coastal cities, in the long run. And just how close are we to exceeding 2 degrees Celsius? Several scenarios used for the draft report project "high confidence" that we'll get there by the end of the century. At that point, seas would continue to rise well beyond the year 2100, and by much more than three feet.

This also implies a substantial melting of the Greenland ice sheet. The draft report adds that during the last interglacial period, the melting of Greenland "very likely" contributed between 1.4 and 4.3 meters of global sea level rise, with additional contributions coming from the melting of Antarctica. If Greenland were to melt entirely, it is estimated that sea level would rise by about seven meters.

Thus, a substantial Greenland melting could also be set in motion by the end of this century, which would eventually result in dramatic sea level increases. To be sure, most of this wouldn't occur during the current century—it would play out on a much longer time scale. But over 1,000 years or more, the draft report says, Greenland could melt almost entirely, and much of the change might be "irreversible." (Granted, the report expresses low confidence about the precise temperature threshold required to bring about a full melting of Greenland.)

Much of the carbon we've emitted will stay in the atmosphere for a millennium…even after we've stopped emitting it. The draft report says that 20 percent of the carbon dioxide currently in the atmosphere will stay there for an almost unimaginably long time—more than 1,000 years. Even if we were to completely cease all greenhouse gas emissions, the draft report adds, warming would continue for "many centuries." "A large fraction of climate change," the document intones, "is thus irreversible on a human time scale." The only way out would be if our emission levels were "strongly negative for a sustained period"—which, to put it mildly, seems highly unlikely.
 In the year 2100, many people reading this right now, your children and grandchildren will be alive then.  Is that what you want to leave them? 


  1. Man made global warming is a myth. All of the serious 2100 talk is centered around Hill Giants. Get in the game!

    1. Hill Giants are imaginary. Man made global warming is not. Please check in with reality.

  2. Anon at 10:40, you can write a check for the 2010 Milwaukee flood, the floods in Duluth last year, the floods in Toronto and Philadelphia last year. Also provide full reimbursement for all damage done to Joplin, MO, OKC, Alabama, and other areas in recent years by tornadoes.

    Also reimburse the families of the 19 firefighters who just died in Arizona, as well as all the property damage all those wild fires are doing.

    We're a world-at-war with climate and the list of damage from ignorance such as yours goes on and on and on.

    When are the thousands of commercial fishing jobs coming back to Lake Michigan.

    "The Decline of a Once-Great Fishery"

    1. And you can split your paycheck with Michael Moore who made reactionary-instigation a thing.

      Spend the rest on a creative writing class. Do it for you.

    2. WoW Anon 3:22... Pull you head out of that sand box you are hiding in and look around you!!!! Get a clue before its to late!

  3. This is the sandbox. Look around YOU.

  4. Gonna reuse and modify a rationale here, if we are right and you are wrong we all will burn for your sins. I don't want to risk the chance at being saved because of ideological buffoonery. The entire population of humans will assuredly be pushed to extinction by starvation, dehydration, disease, or exposure of some fashion. What does it hurt to be better off safe than sorry? As an old Native American saying rightfully summizes, we do not own the Earth, we have it on loan from future generations and must ensure we give it back in equal or greater value.