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Scott Pruitt insincerely asked what's Earth's ideal temperature. Scientists answer

Posted on 17 January 2018 by dana1981

In an interview with Reuters last week, Trump’s EPA administrator Scott Pruitt said,

The climate is changing. That’s not the debate. The debate is how do we know what the ideal surface temperature is in 2100?

Pruitt’s goal is to sow doubt on behalf of his oil industry allies in order to weaken and delay climate policies. Shifting the ‘debate’ toward ‘the ideal surface temperature’ achieves that goal by creating the perception that we don’t know what temperature we should aim for. It’s in line with his boss’ recent ignorant tweet suggesting that “Perhaps we could use a little bit of that good old Global Warming.”

I spoke with a number of climate scientists who agreed that to minimize the risks associated with rapid human-caused climate change, from a practical standpoint the ‘ideal temperature’ is as close to the current one as possible.

Temperature isn’t the issue - temperature change is

Stefan Rahmstorf, Head of Earth System Analysis at the Potsdam Institute for Climate Impact Research pointed out that we’re not concerned about specific temperatures; it’s rapid temperature changes that cause problems:

Pruitt of course is trying to have a strawman debate, distracting from the fact that not a certain temperature as such is better or worse, but that a change from what we are adapted to is a problem, especially a very rapid change - in either direction, cooling or warming, this causes big disruption.

We should not stray too far away from what we and the currently existing ecosystems have evolved for. That is the optimum, simply because it is what we’re highly adapted to, and any major change is going to be very painful.

Civilization developed in a stable climate

Texas Tech’s Katharine Hayhoe agreed, noting that human civilization has developed in the relatively stable climate of the past 10,000 years.

There is no one perfect temperature for the earth, but there is for us humans, and that’s the temperature we’ve had over the last few thousands of years when we built our civilization, agriculture, economy, and infrastructure. Global average temperature over the last few millennia has fluctuated by a few tenths of degrees; today, it’s risen by nearly 1°C and counting.

Why do we care? Because we are perfectly adapted to our current conditions. Two-thirds of the world’s largest cities are located within a metre of sea level. What happens when sea level rises a metre or more, as it’s likely to this century? We can’t pick up Shanghai or London or New York and move them. Most of our arable land is already carefully allocated and farmed. 

What happens when we can no longer grow the crops we used to, as climate shifts and water becomes more scarce in many subtropical areas? We can’t just take over new land: someone else already owns it. What happens when our water resources diminish or even run out? We can’t take over someone else’s water rights without a war.

We care about a changing climate because it exacerbates the risks we face today, and threatens the resources we depend on for our future.

In fact, Hayhoe specifically answered this question in one of her ‘Global Weirding’ videos for PBS:

The Paris climate targets are appropriate

Michael Mann, Distinguished Professor of Atmospheric Science at Penn State also pointed out that we’re approaching some critical temperature thresholds. For example, his research has shown that at warmer temperatures, reproduction of malaria-transmitting parasites increases rapidly.

There are some absolute temperature thresholds that are important when it comes to agriculture (particularly in tropics), coral bleaching, infectious disease, and heat stress (e.g. the tropics becoming essentially unlivable).

So while it’s difficult to say what the “ideal temperature” is, there clearly is a range of temperatures suitable for human civilization and there is a real danger that we’re pushing toward the upper limit of that range.

Naomi Oreskes, Professor of the History of Science and Affiliated Professor of Earth and Planetary Sciences at Harvard similarly noted that according to the peer-reviewed literature on climate change impacts, we’re already headed into dangerous territory:

Of course, there is no ‘ideal’ temperature so we should not accept that framing. We have strong scientific evidence that anything above 2°C is likely to be deeply problematic. Even the roughly 1°C change we have already seen is having measurable, adverse effects.

Click here to read the rest

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Comments 1 to 11:

  1. Yes its a rate of change problem. An ideal temperature is a strawman. Heatwaves will increase, and we cannot adapt quickly enough biologically, so have to expend energy to adapt, diverted form other pressing priorities,  and it will create refugee problems.

    But this will not worry people like Scott Pruit. Pruitt sits in his secure, air conditioned office with his millions of dollars, secure from the effects of climate change, and not caring about anyone apart from his immediate circle of people. You cannot reason with people like Pruitt. The fossil fuel industry now runs the American government. 

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  2. Recommended supplemental reading:

    Climate scientists on Wednesday suggested that they may be able to rule out some of the most dire scenarios of what would happen if greenhouse gas levels in the atmosphere were to double.

    Unfortunately, the same scientists say the best-case scenarios are also probably unrealistic.

    How a doubling of atmospheric greenhouse gases would affect the climate is of tremendous importance, as humans are running out of time to avoid that outcome. With current atmospheric concentrations at 405 parts per million, as opposed to about 280 parts per million before the dawn of the industrial era, the planet is already about halfway there.

    Climate scientists say they may be able to rule out the worst-case scenarios — and the best ones by Chris Mooney, Energy & Environment, Jan 17, 2018

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  3. The problem is: Change/Harm/Uncertainty on a global scale being created by rapid alteration of the living environment of this amazing planet by an unsustainable and damaging human activity.

    The Real question is: How much damage/trouble are the pursuers of Private Interest (trying to personally benefit from the unsustainable and damaging activity) going to get away with creating?

    The debates needs to be: How did we end up in this unsustainable damaging situation? And what changes get the future of humanity out of the damaging unsustainable downward spiral that only looks like progress? Hint - new technological developments may be helpful but are Not the answer.

    The likes of Pruitt appear to be deliberately Unhelpful (potentially deliberately harmful, and potentially deliberately harmful is almost criminal)

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  4. Pruitt: "how do we know what the ideal surface temperature is in 2100"?  Ideal surface temperature 4 C cooler than now.  At that temperature, Eastern U.S. covered under a mile of ice, sea level hundred feet lower than present, wooly mammoth everywhere, plenty meat and skins for all neanderthal.  Good times!  Signed,  Thorg.

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  5. Scott, since sea level and global temperature are closely linked, your question can be reconstructed as, "What it the ideal sea level?" 

    Well, the sea gulls don't care, the fish don't care, even the coral reefs will move effortlessly if the change is gradual.  However one species has trillions of dollars invested in coastal infrastructure.  What is the ideal location for a major port?  Ten meters above sea level?  Ten meters below sea level?  Or right at sea level where it currently exists?

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  6. Scott is happy with his mediocrity : it makes him happy and the elite treat him with softer fingers than they do themselves and their peers because this is infact the first prerequisite for a member of the elite!

    I think that‘s Nietzsche but don’t quote me on it!

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    Moderator Response:

    [JH] Ad hominem snipped.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

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  7. 2ndly, does anyone know if Michael Mann is predicting malaria in Australia yet?

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    [JH] Off-topic nonsense snipped. 

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  8. @ Bozza:

    I understand that Australia is no newcomer to malaria, having eliminated it in the Top End during and after WWII (DDT??).  There is no reason to forget that the disease's name comes from the Latin or Italian, meaning "bad air".  Europe eliminated malaria only recently.

    Malaria is no joking matter, however the above demonstrates that it is probably manageable.  One emerging tool is vaccine, currently being developed in several promising research establishments in Australia and elsewhere.

    Other effects of climate change, such as sea level rise and ocean acidification, may not be so accommodating.

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  9. Dear Moderator:

    Please remove this post and my previous one in response to a comment which has since been removed.

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  10. The article hit the nail on the head.  The best temperature is the one we have adapted to over they past 12,000 years or so.  It is often noted by scientists, looking at past interglacials, how unusual this period has been. Generally, a little before maximum ice melt as we emerge from a glacial, (not an ice age) carbon dioxide begins to drop and that combined with the current Miloankovitch cycle causes snow to begin to accumulate on the high lands of Baffin Island and to spread south.  Reading  Plought Plagues and Petroleum, it looks as if we reversed the steady drop in Carbon dioxide long before the industrial revolution by our agriculture.  We may have been responsible for this remarkably benign period.  Even so we were sliding into a glacial, albeit, more slowly than usual.  Then came along the black death and the extermination by disease of the population of North America.  We were very close and the recovery of the forests  with the draw down of Carbon dioxide, just nudged us into snow accumulation on Baffin Island.  The traces can still be seen in the halo of dead lichens around the highlands.  Our output of Carbon dioxide continued to increase and the process was reversed.  Now we have too much of a good thing and seem to be on the road to kicking ourselves into a dark age or perhaps a stone age.  It is as endlessly fascinating as a good horror movie, to see how incredibly smart we are individually and how incredibly dumb we are in the collective.  The one ring that controls them all is vested interest money in politics.

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  11. Recommended supplemental reading:

    It's misleading to ask what Earth's 'ideal temperature' is. Here's what's really important by Andrew Freedman, Mashable, Feb 14, 2018

    The article is chocked full of quotes from prominent climate scientists.

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