Fire and Ice

Nope, this is not about Robert Frost's poem.  Though, it might be a good time--actually anytime is a good time--to read that.

Fire and ice--in addition to hate that tRump has been spreading--are very much defining the hell that we are currently in.  Glaciers and ice sheets are melting.  The Amazon is on fire.  The end of the world is nigh!

What if climate scientists had been underestimating the pace and impacts of climate change?

When new observations of the climate system have provided more or better data, or permitted us to reevaluate old ones, the findings for ice extent, sea level rise and ocean temperature have generally been worse than earlier prevailing views.

For a moment, set aside any views that you may have about climate change.  Do not pause to think about the science and the complexity of understanding climate change.  Ask yourself a simple question.  Over the years, have you read any news item that makes you feel that there has been deluge of good reports that the natural world around us is getting healthier and better?

What if the story is that scientists have been underplaying the climate change issue all along?  And not because of any conspiracy, but because the scientific methods compels them to be a lot more cautious and conservative in their estimates?

Almost four years ago, during the monsoon season, Chennai experienced rains like it never has.  The reservoirs filled up fast and water had to be released in order to prevent any damage to the dams.  This sent more water into the already flooded canals and rivers and the city was flooded.  Most of the city was cut off.

A few weeks after that, in the column that I wrote, I linked this to climate change, and that the Chennai flood was a result of climate weirding.  Pat came a response from an old high school friend, who is a climate scientist.  He wrote to me that scientists were working on this attribution and that they did not have conclusive evidence, yet. (Update: His reaction was to a column later--after the Cyclone Vardah that I wrote about.)

That is how scientists work.  While their personal feelings might allow them to make the leap similar to what I did, professional integrity requires them to seek the evidence first.

Which is also why I have always felt that maybe climate scientists have been underestimating the impacts.  In a class for freshman students this fall, I  planned to make them think about this aspect--that the news about climate change is telling a wrong story, and that it really is worse than what we think it is.

This is also why the Scientific American piece appeals to me.

Among the factors that appear to contribute to underestimation is the perceived need for consensus, or what we label univocality: the felt need to speak in a single voice. Many scientists worry that if disagreement is publicly aired, government officials will conflate differences of opinion with ignorance and use this as justification for inaction. Others worry that even if policy makers want to act, they will find it difficult to do so if scientists fail to send an unambiguous message. Therefore, they will actively seek to find their common ground and focus on areas of agreement; in some cases, they will only put forward conclusions on which they can all agree.

Primarily because the overwhelming majority of the population is not scientists and it is difficult for us to wrap our minds about ideas like statistical significance and confidence limits and probability and ... so, "The drive toward consensus may therefore be an attempt to present the findings of the assessment as matters of fact rather than judgment."

Consider a case in which most scientists think that the correct answer to a question is in the range 1–10, but some believe that it could be as high as 100. In such a case, everyone will agree that it is at least 1–10, but not everyone will agree that it could be as high as 100. Therefore, the area of agreement is 1–10, and this is reported as the consensus view. Wherever there is a range of possible outcomes that includes a long, high-end tail of probability, the area of overlap will necessarily lie at or near the low end. Error bars can be (and generally are) used to express the range of possible outcomes, but it may be difficult to achieve consensus on the high end of the error estimate.

Underestimation happens.

And, therefore, this: "They may also consciously or unconsciously pull back from reporting on extreme outcomes."  Which is exactly how my friend responded to my column on the flood in Chennai and climate change.

So, in case nobody ever warned you ... lemme do this for you.  After all, I am General Malaise!  The pace of climate change is far worse than you think it is.