I Will Be Speaking in Massachusetts March 7
I will be speaking at Pruyne Lecture Hall at Amherst College in Amherst, Massachusetts (about an hour north of Hartford, CT and 90 minutes west of Boston) at 7PM on March 7. I will be using the opportunity to roll out version 3.0 of my climate talk. My understanding is that it is open to the public, so I encourage readers who are nearby to attend.
Logan Durand:
I noticed a slight error in the current version of "Catastrophe Denied" on YouTube. You refer to MM05 (GRL) feeding "white noise" into MBH98's short-centered principal components analysis. In fact, MM05 used 'red noise', which is a random walk (each psuedoproxy year representing the previous year plus or minus a random number), whereas 'white noise' represents truly random, independent values. Although the impact to the layman is the same, the difference is of technically important, as the short-centered PCA is only prone to 'cherry-picking' hockey-sticks in the case of a random walk, rather than white noise. This is due to the fact that only red noise can generate a data series with a persistent deviation from zero during the range used for centering, which can then heavily weighed when determining the principal components.
February 15, 2013, 10:36 pmFelineCannonball:
Do you look much at the counter-skeptic literature when you prep for this stuff? I watched your 2009 talk, and in a way a lot of your points are straight out of the climate literature, detailing complexities and results counter to those touted by the most alarmist non-scientist activists. But some of the charts and discussion from the 2009 talk are themselves based on some embarrassing omissions, embarrassingly out-of-date stuff, or purposely biased charts. There's certainly plenty of room for uncertainty but I think you could acknowledge mainstream scientific opinion a little better.
So. . . Virtually no one assumes a 10x warming multiplier. No one assumes a Venus type run-away greenhouse. We're talking a complex system oscillating between multiple quasi-stable states (multiple connected cooking woks on a bouncing tilting platform?). Everyone acknowledges parts of the northern hemisphere were warm from 950-1250 AD, but as we keep collecting data, there really is no evidence that it was a strong globally distributed warming event. The heat-island effect on instrumental temperature readings has been addressed pretty well in modern literature and they at least believe they have a handle on it: http://www.agu.org/pubs/crossref/pip/2012JD018509.shtml . The term "climate change" reflects the fact that different climate states have diverse regional impacts that may include warming, stasis, cooling, drying, etc. "Global warming" is not predicted under any model to cause a uniform increase in temperature without significant alteration of atmospheric or oceanic circulation. Direct effects are pretty obviously expected to impact Arctic temperatures the most and nothing in the concept rules out changes in circulation that create local regions of cooling or desertification or "swampification", elsewhere. Stratospheric cooling is a very direct effect. The academic use of the term "climate change" is meant to reflect this diversity of regional impacts that might be counter-intuitive to those living in tropical or temperate regions. Yes CO2 is a "weak" greenhouse gas. The special thing about CO2 is the long time that pulses are sustained in the atmosphere. Nothing says it necessarily initiates warming (although it can), but once significant shifts in CO2 occur -- perhaps as a secondary effect, it is a forcing that will last long enough for the larger system to reach equilibrium consistent with it. H20 in the atmosphere is a very rapidly adjusting system. Methane has a half-life of 8-10 years. No one expects all climate feedbacks to respond rapidly within 10 years of CO2 forcing. Shifting oceanic temperatures and sea floor temperatures and deep soil temperatures (McKenzie Delta sediment at 1000 feet depth has a lot of quasi-stable carbon and it's temp is controlled by atmospheric temp from more than a millennium ago -- it takes a long time for heat to conduct through dirt). Glacier retreat is not instantaneous, soil and sediment carbon doesn't jump to a new equilibrium over night, ecosystems take centuries to adjust to new temperature and hydrological regimes, etc. When we look at CO2 multipliers in geological time (in which the actual transition is generally difficult to assess) we see an apparent multiplier of 2.5x to 5x. This is certainly not an instantaneous reaction to CO2 (and once again CO2 is generally not an initial driver geologically). It just says that equilibrium climate systems after a doubling of CO2 (within the range observed over the last 60 million years or so) have a myriad of associated feedbacks that result in that apparent multiplier before and after the transition phase. Water vapor responds quickly but a lot of other shifts are not. Among the feedbacks to consider are indirect impacts on the carbon cycle (soil carbon, sediment carbon, ocean temperature, ecosystem shifts) that make it pretty unclear just what the atmospheric CO2 level will be as a result of our inputs when things settle down in a few hundred years.
I'm not an alarmist, don't think the human race will get wiped out, and actually don't think we have a political system capable of shutting down or controlling CO2 generation if we wanted to. Climate change will cause shifts in the economy, agriculture, extinctions, etc. and probably shouldn't be ignored from an adaptive and planning perspective. But I like your point about the attention not spent on backyard environmental problems (many of which are easily and cheaply dealt with and might even aid when it comes to climate change adaptation). And a revenue neutral carbon tax probably isn't that stupid of an idea in any circumstance -- in as much as it can make us more efficient and resilient to spikes in energy costs and less dependent on foreign trade that might be tenuous in the face of future wars, unfriendly foreign governments, etc. Certainly beats free heating oil handouts for poor people in uninsulated homes in New England. That doesn't make any type of economic sense.
The way I generally think about it, your stuff or Al Gore's stuff is sophisticated enough that it makes a decent assignment for undergrads to pour through it looking for mistakes and missing nuance. But both are either biased by political views or a misunderstanding of the detailed science.
February 16, 2013, 11:52 amdc:
you lost us at "runaway venus greenhouse"...go look up atmospheric pressure for chrissakes!
February 20, 2013, 11:15 amGaia:
The entire Amherst MA area is a fever swamp of Marxist ideology. They will not debate you but they will attempt to silence you. Be prepared to be demonized as some sort of flat earth, anti science, religious nut or racist hater.
March 3, 2013, 5:09 am