Lately there has appeared the hypothesis that global warming is causing global cooling. Versions of this have been around for at least 10 years. They involve a theory that fresh water melted from ice enters certain oceans. Its density differs from salt water. The mixing affects temperatures of surface water and the atmosphere.
It’s a theory. It’s only a theory. It’s not fact. Its validity is questionable. Theories are contestable. Climate science is unsettled, very unsettled. The theories of scientists in this field compete with one another. Knowledge is not firm concerning the factors that determine climate in the earth as a whole and in its various regions. Understanding of climate change is elusive. Just because scientific work is being done on climate doesn’t mean that there is highly reliable scientific knowledge upon which mankind can place huge bets. If global warming causes global cooling, does the reverse happen too? Are there cycles? If so, how long? What are the driving variables?
It is rather easy to search using google and find alternative theories posed by climate scientists. One finds a theory that the salinity of the Mediterranean Sea has a large impact on climate. Another theory points to the Siberian ice cover. One finds theories of why the Arctic ice mass undergoes its fluctuations and why the Antarctic ice cap is larger than ever. One finds alternative theories of why ice ages occurred thousands of years ago. If scientists can’t understand or haven’t yet figured out what caused past climate changes, how sure can they or we be about their theories of current and future changes? Not very. Even when scientists group around a given theory for the purpose of exploring its implications and perhaps leading them to discoveries and deeper questioning, one cannot be sure that a theory is true or won’t be found wanting in some or many respects, or else is already wanting in major respects but is the only game in town or the most popular game in town.
Do politicians who promote currently popular theories of global warming have any idea of the unsettled status of climate science or any idea of how science actually proceeds? They don’t seem to. They don’t express the appropriate skepticism and doubts. They act as if they are sure. Al Gore has always acted as if he were dead certain about global warming. He’s been so sure that he’d make firm predictions and recommend enormous economic changes. He’s an example of the ignorance of politicians when it comes to scientific matters. Can we trust scientists to be more objective? Unfortunately, we cannot, and especially not when their incentives are skewed by government grants.
8:01 am on September 24, 2014
