I have to write about the new UN climate report that is all over the news this morning. There is not much to say about the substance of the report, as none of it is news to those who have been following climate impacts over the past 20 years. This is to be expected in a report that has to be agreed unanimously in every detail among 100 nations. The authors are forced to weigh the benefits of mentioning a possible impact against the greater ease of remaining silent on a topic that is in some doubt. The result of that heavy political environment is a policy report that is very cautious and reserved when it points to future impacts of climate change. The impacts mentioned in the report are essentially those that are already set in stone. It is, in all likelihood, ten years too late to prevent any of them, aside from the obvious measures of getting people out of the way.
The UN report is valuable for remediation discussions that must work within severe economic constraints, but for planning purposes we should be listening to the alarmists too. There will be impacts that go beyond those that are obvious now. With change, there always consequences that are not obvious until after they occur. Climate alarmists are, for the most part, the people who can see impacts coming, even if they cannot forecast with the precision that a political process requires. We know, to cite just one example, that we are facing a global sea level rise of 7 meters somewhere out on the planning horizon. It will happen regardless of future industrial greenhouse gas emissions. The likely time for this degree of sea level rise is 1 to 2 centuries from now. That is a lot of uncertainty, so much that the UN report does not attempt to quantify the amount or timing of sea level rise, but the timing is a minor detail. As long as we continue to build buildings, roads, tunnels, bridges, pipelines, and other facilities that we know with a good degree of certainty will be submerged within their potential useful lives, we are drawing up future disasters. As a very simple example, a flood-plain shopping center currently under construction 4 meters above sea level will with certainty be demolished by flood waters in a storm before 2125, and perhaps much sooner. We can start to redirect ourselves from the most immediate of those planned disasters even though, at this point, we do not know whether it is us or our grandchildren who will be affected.
Some of the policy discussions surrounding climate change are based on plans to limit global temperature increase to 2 kelvins, or 2° Celsius. It is already too late in a political sense for that. In theory it could be done but we would have to completely stop burning all fuel by around 2040 — how? There are discussions about how to save the Greenland Ice Sheet from melting. If that could be done, it would reduce sea level rise by 7 meters, but it is too late for that too. In the current climate conditions, all the ice in Greenland will melt away in less than 1,000 years, but a better guess based on past greenhouse gas emissions only is 300 years. It is painful to observe policy discussions that are so far behind the flow of events, but at least policy discussions are taking place, and with that, there is the hope that the discussions could catch up with what has already happened.
