Ckimate change and extreme events

This is not a new topic for this section of PriusChat. But I bring to your attention an editorial in the journal "Weather, Climate, and Society" just plug in the digital object identifier

doi:10.1175/WCAS-D-14-00005.1

It's free to download. the authors caution (quite reasonably) that extreme events always have and always will take place. We need to prepare for them in advance, which will often cost less than mopping up after. Entangling the concept with climate change per se will probably just bog down the discussion. Worse, some slowing of CO2 increase could lead to a false sense of security that 'now we are done with extreme events'.

All good advice it seems to me. All quite in line with (the best of) Pielke's thinking (the younger one), which I have praised here before.

 

Atmospheric water vapor plays a major role in the 'greenhouse effect' that keeps the Earth's surface much warmer than the moon's. For it to contribute to additional warming, it would need to increase. We've discussed here before that water vapor may be increasing slowly, but it is a difficult measurement.

Briefly, you are looking for a small change in a large value, and that value varies widely across regions.

For it to increase substantially, increased surface evaporation would have to go unbalanced by increased rain or snowfall somewhere. Could happen, does not seem to be happening yet. As climate/CO2 sensitivity is supposed to be amplified by water vapor increases, maybe it won't be (so much). So, maybe the lower CO2 sensitivity estimates are more reasonable. We are likely to know that very well with a few more decades of T measurements, even if the climate models don't improve enough to make the call.

Meanwhile, I will take issue with the notion that folks don't talk about this. They do:

Ancient Indonesian climate shift linked to glacial cycle -- ScienceDaily

And it's not just talk. Serious sediment coring and isotope and geochemical work. Water vapor, at least, matters a lot for glacial / interglacial cycles.

 

Wxman, I understand that radiosondes have used a variety of RH sensors over the years. That variation among individuals and intercalibrations associated with hardware changes have compromised detection of long term patterns. Have you experience in this area?

 

I used Vaisala capacitive humidity sensors on tower-based installations. Take any 'N' of them and you will obtain a like number of different readings, including one that is quite different. This is not a knock on the manufacturer. If you want a reliable time series, be prepared to put in some effort.

The original intent of radiosonde sampling was never to create long time series, so I am prepared to forgive them.

Meanwhile while careful chartmanship can show that extreme events seem not to be increasing, that will only comfort a few who might be bringing an agenda to the table. Instead I go with the first-linked authors who essentially state that it is cheaper to prepare than repair.

Clever, that. Too bad The Hindu newspaper penned it first in 2006.

 

There have certainly been significant regional changes in precip and streamflow. With some areas getting wetter and others getting drier, the net global effect is not different from zero.

But regional hydrology is what matters I suppose.