A couple of weeks ago, New York Times science writer Andrew Revkin wrote a piece titled “Arctic Melt Unnerves the Experts” in which he described this year’s record low Arctic summer sea ice extent and the how the dramatic decline over last year had caught many sea-ice scientists by surprise. Revkin goes on to interview a variety of experts on the topic of sea ice, most of which realize that some (most) of the sea ice decline observed over the past several decades is likely related to anthropogenic changes to the earth’s climate, while admitting that undoubtedly, some natural (non-human-influenced) processes likely contributed to the decline as well.
Revkin starts out by noting “astonished by the summer’s changes [in ice extent], scientists are studying forces that exposed one million square miles of open water—six Californias—beyond the average since satellites started measurements in 1979.”
And then he continues:
Proponents of cuts in greenhouse gases cited the meltdown as proof that human activities are propelling a slide toward climate calamity.
Arctic experts say things are not that simple. More than a dozen experts said in interviews that the extreme summer ice retreat had revealed at least as much about what remains unknown in the Arctic as what is clear. Still, many of those scientists said they were becoming convinced that the system is heading toward a new, more watery state, and that human-caused global warming is playing a significant role.
For one thing, experts are having trouble finding any records from Russia, Alaska or elsewhere pointing to such a widespread Arctic ice retreat in recent times, adding credence to the idea that humans may have tipped the balance. Many scientists say the last substantial warming in the region, peaking in the 1930s, mainly affected areas near Greenland and Scandinavia.
Depending on what Revkin meant by “recent times,” perhaps we could help him out as to where he may look in order to find out some information indicating that “widespread Arctic ice retreat” has occurred without any human help. If Revkin meant “since satellites started measurements in 1979” then, he probably has that covered, but if by “recent” he meant within the past 100 years or so, then maybe we could suggest a few other avenues to investigate.
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