Originally Posted by Andy H.
There has been a consensus since about 1995 among the scientific community that climate change is real, its happening, and that its caused by CO2 from human activities.
Generally love your posts, Andy, but I would like to assert that "caused by CO2 from human activities" is not necessarily clear or agreed upon. When one attributes causation, one doesn't necessarily mean 'primary' or 'predominately'. Science agrees CO2 is a factor, but not on its primacy.
A factor under-emphasized by people who advocate the critical need to reduce CO2 emissions is the extremely limited amount of information we have on our life-giving sun. In capability, our sun's energy output could easily bear far more pressure on the earth's environment than any single factor (indeed, when it transitions to burning helium, it will grow in size to consume the first four planets in the solar system).
We know very little about the sun's mechanics, let alone the ability to measure much of the sun's energy output. We know from geological data that the earth was once much, much hotter (and that Antartica was not always an ice-ball). We've only theories as to why those changes occurred. We have very interesting data on the mini-ice age of the 17th century, but more questions than understanding because calibration of equipment from that era leaves so much to be desired. Indeed, our ability to measure atmospheric stuff tends to improve at a rate greater than linear improvement due more to technology than human understanding. Thus, data from a century ago are placed into question . This is a major problem for scientific inquiry. Older data becomes less reliable the older it is, and two or three centuries of data is completely inadequate in the study of an entire planetary atmosphere.
To the point that you argue about insurance companies and budget planners now taking into account the variables of global warming as they may impact calamitous weather phenomenon, I feel you assert too much scientific understanding to those actors. And this leads into my conclusionary points about the debate on global warming.
That insurance companies and planners take greater account of catastrophic whether phenomenon in planning is a factor having much more to do with risk management decision-making than it has to do with acceptance of global warming. It is in the interests of planning agencies to mitigate the impact of high consequence events even when the probabilities of those events occurring are astronomically small. Particularly in this country, where the cost is measured in human lives, we spend a great deal of money to protect life. This is not necessarily a factor of acceptance of (let alone understanding of) scientific models: it's a matter of risk mitigation.
Now this brings me to my conclusion, and something non-science folk really ought to consider. Science is an endeavor of incremental increases in knowledge, and (unlike so-called divinely revealed 'truth') is subject to revision in the face of new evidence. Clearly our atmosphere is a vastly complex mechanism that defies our current capacity to model.
But a logical human need not accept that global warming is a) occurring, and b) caused predominately by human activity to recognize the risk associated with atmospheric change. Because the risk of atmospheric change could radically impact human life, by any number of direct or indirect means such as loss of agricultural capacity, damage to lower parts of the food chain, or radical changes to weather patterns, it is prudent to ask the following question:
When do we decide it is necessary to act in the presence of incomplete information?
It's not a bad idea to act on the information we have now to see how we can affect our climate in self-preservational ways (or at least I don't think so).