<\/p>\n
It is nearly 8000 words, so while you should read the whole thing,
\nI’ll post some of the highlights below. I’ll also throw some links to
\nthe scientific and economic literature that the NYT, in its infinite wisdom\/stupidity, refuses to include.<\/p>\n
<\/p>\n
The essay isn’t primarily about the science, but this is what Krugman has to say on that, starting with the opening paragraph:<\/p>\n
If you listen<\/strong> to climate scientists—and despite the relentless campaign to discredit their work, you should—it is long past time to do something about emissions of carbon <\/p>\n This is an article on climate economics, not climate science. But <\/p>\n Second, climate models predicted this well in advance, even getting <\/p>\n Yet that’s not the conclusion you might draw from the many media <\/p>\n And this brings me to my third point: models based on this <\/p>\n Now, despite the high credibility of climate modelers, there is <\/p>\n At this point, the projections of climate change, assuming we <\/p>\n Furthermore, changes in average temperature will by no means be the <\/p>\n But there are at least two reasons to take sanguine assessments of For what the science says we risk if we stay anywhere near our current path of unrestricted emissions, see:<\/p>\n Nature Geoscience study: Oceans are acidifying 10 times faster today than 55 million He has a discussion of the low cost of action:<\/p>\n Just as there is a rough consensus among climate <\/p>\n Such figures typically come from a model that combines all sorts of <\/p>\n There are, of course, a number of ways this kind of modeling could <\/p>\n But while it’s unlikely that these models get everything right, it’s I <\/strong>have links to some of the key literature on this here:<\/p>\n Introduction And of course he discusses what scientific uncertainty means for economic modeling:<\/p>\n Finally and most important is the matter of uncertainty. <\/p>\n You might think that this uncertainty weakens the case for action, but it actually strengthens it. As Harvard<\/a>‘s <\/p>\n Weitzman argues—and I agree—that this risk of catastrophe, For more on Weitzman, see<\/p>\n Harvard Krugman’s key conclusions are:<\/p>\n Stern’s moral argument for loving unborn generations as <\/p>\n If it does, the economic analysis will be ready. We know how to Hear! Hear!<\/p>\n Related Links:<\/strong><\/p>\n The problem with a green economy: economics hates the environment<\/a><\/p>\n Revkin wants to talk ‘energy quest’ not ‘climate crisis’<\/a><\/p>\n
\ndioxide and other greenhouse gases. If we continue with business as
\nusual, they say, we are facing a rise in global temperatures that will
\nbe little short of apocalyptic. And to avoid that apocalypse, we have
\nto wean our economy from the use of fossil fuels, coal above all …<\/p>\n
\nbefore we get to the economics, it’s worth establishing three things
\nabout the state of the scientific debate. The first is that the planet
\nis indeed warming. Weather fluctuates, and as a consequence it’s easy
\nenough to point to an unusually warm year in the recent past, note that
\nit’s cooler now and claim, “See, the planet is getting cooler, not
\nwarmer!” But if you look at the evidence the right way —taking
\naverages over periods long enough to smooth out the fluctuations—the
\nupward trend is unmistakable: each successive decade since the 1970s
\nhas been warmer than the one before.<\/p>\n
\nthe magnitude of the temperature rise roughly right. While it’s
\nrelatively easy to cook up an analysis that matches known data, it is
\nmuch harder to create a model that accurately forecasts the future. So
\nthe fact that climate modelers more than 20 years ago successfully
\npredicted the subsequent global warming gives them enormous credibility.<\/p>\n
\nreports that have focused on matters like hacked email and climate
\nscientists’ talking about a “trick” to “hide” an anomalous decline in
\none data series or expressing their wish to see papers by climate
\nskeptics kept out of research reviews. The truth, however, is that the
\nsupposed scandals evaporate on closer examination, revealing only that
\nclimate researchers are human beings, too. Yes, scientists try to make
\ntheir results stand out, but no data were suppressed. Yes, scientists
\ndislike it when work that they think deliberately obfuscates the issues
\ngets published. What else is new? Nothing suggests that there should
\nnot continue to be strong support for climate research.<\/strong><\/p>\n
\nresearch indicate that if we continue adding greenhouse gases to the
\natmosphere as we have, we will eventually face drastic changes in the
\nclimate. Let’s be clear. We’re not talking about a few more hot days in
\nthe summer and a bit less snow in the winter; we’re talking about
\nmassively disruptive events, like the transformation of the
\nSouthwestern United States into a permanent dust bowl over the next few
\ndecades.<\/strong><\/p>\n
\nstill tremendous uncertainty in their long-term forecasts. But as we
\nwill see shortly, uncertainty makes the case for action stronger, not
\nweaker. So climate change demands action …<\/p>\n
\ncontinue business as usual, cluster around an estimate that average
\ntemperatures will be about 9 degrees Fahrenheit higher in 2100 than
\nthey were in 2000. That’s a lot—equivalent to the difference in
\naverage temperatures between New York and central Mississippi. Such a
\nhuge change would have to be highly disruptive. And the troubles would
\nnot stop there: temperatures would continue to rise.<\/p>\n
\nwhole story. Precipitation patterns will change, with some regions
\ngetting much wetter and others much drier. Many modelers also predict
\nmore intense storms. Sea levels would rise, with the impact intensified
\nby those storms: coastal flooding, already a major source of natural
\ndisasters, would become much more frequent and severe. And there might
\nbe drastic changes in the climate of some regions as ocean currents
\nshift. It’s always worth bearing in mind that London is at the same
\nlatitude as Labrador; without the Gulf Stream, Western Europe would be
\nbarely habitable.<\/p>\n
\nthe consequences of climate change with a grain of salt. One is that,
\nas I have just pointed out, it’s not just a matter of having warmer
\nweather—many of the costs of climate change are likely to result from
\ndroughts, flooding, and severe storms. The other is that while modern
\neconomies may be highly adaptable, the same may not be true of
\necosystems. The last time the earth experienced warming at anything
\nlike the pace we now expect was during the Paleocene-Eocene Thermal
\nMaximum, about 55 million years ago, when temperatures rose by about 11
\ndegrees Fahrenheit over the course of around 20,000 years (which is a
\nmuch slower rate than the current pace of warming). That increase was
\nassociated with mass extinctions, which, to put it mildly, probably
\nwould not be good for living standards …<\/p>\n
\nyears ago when a mass extinction of marine species occurred<\/a>
\nM.I.T. doubles its 2095 warming projection to 10 degrees F – with 866 ppm and Arctic warming of 20 degrees F<\/a>
\nOur
\nhellish future: Definitive NOAA-led report on U.S. climate impacts
\nwarns of scorching 9 to 11 degrees F warming over most of inland U.S. by 2090
\nwith Kansas above 90 degrees F some 120 days a year—and that isn’t the worst
\ncase, it’s business as usual!<\/a>
\nScience:
\nCO2 levels haven’t been this high for 15 million years, when it was 5
\nto 10 degrees F warmer and seas were 75 to 120 feet higher—“We have shown
\nthat this dramatic rise in sea level is associated with an increase in
\nCO2 levels of about 100 ppm.”<\/a>
\nAn introduction to global warming impacts: Hell and High Water <\/a><\/p>\n
\nmodelers about the likely trajectory of temperatures if we do not act
\nto cut the emissions of greenhouse gases, there is a rough consensus
\namong economic modelers about the costs of action. That general opinion
\nmay be summed up as follows: Restricting emissions would slow economic
\ngrowth—but not by much. The Congressional Budget Office,
\nrelying on a survey of models, has concluded that Waxman-Markey “would
\nreduce the projected average annual rate of growth of gross domestic
\nproduct between 2010 and 2050 by 0.03 to 0.09 percentage points.”<\/strong> That is, it would trim average annual growth to 2.31 percent, at worst,
\nfrom 2.4 percent. Over all, the Budget Office concludes, strong
\nclimate-change policy would leave the American economy between 1.1
\npercent and 3.4 percent smaller in 2050 than it would be otherwise. And
\nwhat about the world economy? In general, modelers tend to find that
\nclimate-change policies would lower global output by a somewhat smaller
\npercentage than the comparable figures for the United States. The main
\nreason is that emerging economies like China currently use energy
\nfairly inefficiently, partly as a result of national policies that have
\nkept the prices of fossil fuels very low, and could thus achieve large
\nenergy savings at a modest cost. One recent review of the available
\nestimates put the costs of a very strong climate policy—substantially
\nmore aggressive than contemplated in current legislative proposals—at
\nbetween 1 and 3 percent of gross world product.<\/p>\n
\nengineering and marketplace estimates. These will include, for
\ninstance, engineers’ best calculations of how much it costs to generate
\nelectricity in various ways, from coal, gas and nuclear and solar power
\nat given resource prices. Then estimates will be made, based on
\nhistorical experience, of how much consumers would cut back their
\nelectricity consumption if its price rises. The same process is
\nfollowed for other kinds of energy, like motor fuel. And the model
\nassumes that everyone makes the best choice given the economic
\nenvironment—that power generators choose the least expensive means of
\nproducing electricity, while consumers conserve energy as long as the
\nmoney saved by buying less electricity exceeds the cost of using less
\npower in the form either of other spending or loss of convenience.
\nAfter all this analysis, it’s possible to predict how producers and
\nconsumers of energy will react to policies that put a price on
\nemissions and how much those reactions will end up costing the economy
\nas a whole.<\/p>\n
\nbe wrong. Many of the underlying estimates are necessarily somewhat
\nspeculative; nobody really knows, for instance, what solar power will
\ncost once it finally becomes a large-scale proposition. There is also
\nreason to doubt the assumption that people actually make the right
\nchoices: many studies have found that consumers fail to take measures
\nto conserve energy, like improving insulation, even when they could
\nsave money by doing so.<\/p>\n
\na good bet that they overstate rather than understate the economic
\ncosts of climate-change action. That is what the experience from the
\ncap-and-trade program for acid rain suggests: costs came in well below
\ninitial predictions. And in general, what the models do not and cannot
\ntake into account is creativity; surely, faced with an economy in which
\nthere are big monetary payoffs for reducing greenhouse-gas emissions,
\nthe private sector will come up with ways to limit emissions that are
\nnot yet in any model.<\/strong><\/p>\n
\nto climate economics: Why even strong climate action has such a low
\ntotal cost—one tenth of a penny on the dollar<\/a>
\nDespite
\nits many flaws, EIA analysis of climate bill finds 23 cents a day cost
\nto families, massive retirement of dirty coal plants and 119 GW of new
\nrenewables by 2030—plus a million barrels a day oil savings<\/a>
\nNew
\nEPA analysis of Waxman-Markey: Consumer electric bills 7 percent lower in 2020
\nthanks to efficiency—plus 22 GW of extra coal retirements and no new
\ndirty plants<\/a>
\nThe triumph of energy efficiency: Waxman-Markey could save $3,900 per household and create 650,000 jobs by 2030<\/a><\/p>\n
\nWe’re uncertain about the magnitude of climate change, which is
\ninevitable, because we’re talking about reaching levels of carbon
\ndioxide in the atmosphere not seen in millions of years. The recent
\ndoubling of many modelers’ predictions for 2100 is itself an
\nillustration of the scope of that uncertainty; who knows what revisions
\nmay occur in the years ahead. Beyond that, nobody really knows how much
\ndamage would result from temperature rises of the kind now considered
\nlikely.<\/p>\n
\nMartin Weitzman has argued in several influential papers, if there is a
\nsignificant chance of utter catastrophe, that chance—rather than what
\nis most likely to happen—should dominate cost-benefit calculations.
\nAnd utter catastrophe does look like a realistic possibility, even if
\nit is not the most likely outcome.<\/p>\n
\nrather than the details of cost-benefit calculations, makes the most
\npowerful case for strong climate policy. Current projections of global
\nwarming in the absence of action are just too close to the kinds of
\nnumbers associated with doomsday scenarios. It would be irresponsible—it’s tempting to say criminally irresponsible—not to step back from
\nwhat could all too easily turn out to be the edge of a cliff.<\/p>\n
\neconomist: Climate cost-benefit analyses are “unusually misleading,”
\nwarns colleagues “we may be deluding ourselves and others”<\/a><\/p>\n
\nwe love ourselves may be too strong, but there’s a compelling case to
\nbe made that public policy should take a much longer view than private
\nmarkets. Even more important, the policy-ramp prescriptions seem far
\ntoo much like conducting a very risky experiment with the whole planet.
\nNordhaus’s preferred policy, for example, would stabilize the
\nconcentration of carbon dioxide in the atmosphere at a level about
\ntwice its preindustrial average. In his model, this would have only
\nmodest effects on global welfare; but how confident can we be of that?
\nHow sure are we that this kind of change in the environment would not
\nlead to catastrophe? Not sure enough, I’d say, particularly because, as
\nnoted above, climate modelers have sharply raised their estimates of
\nfuture warming in just the last couple of years. So what I end up with
\nis basically Martin Weitzman’s argument: it’s the nonnegligible
\nprobability of utter disaster that should dominate our policy analysis.
\nAnd that argues for aggressive moves to curb emissions, soon …<\/p>\n
\nlimit greenhouse-gas emissions. We have a good sense of the costs—and
\nthey’re manageable. All we need now is the political will.<\/p>\n