11 March 2013

Whom to believe?

In the continuing controversy over climate change it is difficult to sort out the validity of conflicting reports. Here, for example, is a Financial Post column by Lawrence Solomon: Not easy being green. According to Solomon,
Arctic ice has made a comeback, advancing so rapidly that the previous decade saw less ice at this time of the year than exists today. And previously balmy Arctic temperatures just nose-dived, according to the Danish Meteorological Institute, which has tracked Arctic temperatures since 1958.

Alarmists shudder when looking south, too, at the stats from Antarctica. There the sea ice extent started growing early this year, and the ice cover remains stubbornly above average. All told, the global sea ice — including both polar caps — now exceeds the average recorded since 1979, when satellites began their measurements.

But then we read this from Emily E. Adams: Where Has All the Ice Gone? Here's Adams:

In September 2012, sea ice in the Arctic Ocean shrank to a record low extent and volume. The region has warmed 2 degrees Celsius (3.6 degrees Fahrenheit) since the 1960s—twice as much as lower latitudes. With less snow and ice to reflect the sun’s rays and with more exposed ocean to absorb heat, a vicious cycle leads to even warmer temperatures. Thinner ice combined with rising temperatures makes it increasingly difficult for the sea ice to recover. The historically ever-present white cap at the top of the globe could disappear entirely during the summer within two decades. . . .

While Greenland’s ice loss is astonishing, on the other side of the globe, parts of Antarctica’s vast ice sheet may be even less stable. The continent is flanked by 54 major ice shelves, which act as brakes slowing the movement of ice in land-based glaciers out to sea. Twenty of them show signs of thinning and weakening, which translates into accelerated ice loss. After the 3,250-square-kilometer Larsen B Ice Shelf collapsed in 2002, for instance, the glaciers it was bracing flowed up to eight times faster than before. The most dramatic thinning is in West Antarctica.

Which is right? Obviously they cannot both be. The two reports are separated by only a week, yet their respective accounts as to what is happening to the polar ice caps could not be more divergent. As a complete layman in the field, I am incompetent to judge the veracity of the two reports, which I am certain is true of most other readers as well.

However, in the absence of certainty on the issue, our political leaders must still make policies while weighing in the balance the various conflicting considerations at stake. The balance will never be perfect, of course, but in general it seems to me that, even if anthropogenic global warming is not occurring, we still have an obligation to pursue policies to protect our physical environment, both for the sake of future generations and in recognition of our responsibility before God for his creation. We may not be able to settle the debate, but it seems wise to err on the side of caution and of minimizing the environmental risks to our descendants.

1 comment:

  1. Yes, both articles were written within weeks of each other, but they are speaking of ice conditions months apart.

    The policy institute article is speaking re: "In September 2012, sea ice in the Arctic Ocean shrank to a record low..." [This is just at the time of transition when ice is soon to reform after the summer.]

    The POST article is speaking of ice conditions months later in the winter.

    I heard one noted climate scientist say that it used to be standard text book knowledge that the main cause of sea ice disappearing was wind.

    Here is NASA news that shows the storm that caused that ice loss:
    http://wattsupwiththat.com/2012/09/24/nasa-on-arctic-sea-ice-record-low-storm-wreaked-havoc-on-the-arctic-sea-ice-cover/

    The 'record loss' spoken of before was since the satellite record began in 1979. In geologic time that is spit in the ocean. Other records show such conditions in other eras.

    A long but worthwhile discussion between two noted climate scientists, puts things in perspective: http://www.youtube.com/watch?v=gJwayalLpYY

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