In a previous post, Global Warming Signal in Sea Surface Temperature Data, I looked at a small part of a paper co-authored by Dr. Roger Pielke. I focused by discussion on their rotated EOF analysis, and its implications. The problem is that their data only went to the year 2000.

In this post, I’ll redo the analysis for the last 50 years; that is from 1957 through 2007. The data I used is freely available from NOAA: Extended Reconstructed Sea Surface Temperature (SST) V2. This is 2 degree gridded data. The original data extends back until the 1850s - how they aquired reliable global SST data in the 1800s is unknown to me. But since I’m just using the last 50 years, it should be okay. I don’t recall what Castro et al. used in their analysis, but it would necessarily be a similar dataset.

Also, they used a rotated EOF analysis. I use a ‘regular’ EOF analysis, mostly because I couldn’t get my varimax rotation function to work properly. The problem, as always, is that I didn’t write the varimax rotation function and it’s not well documented. After spending a few hours trying to get it to work this weekend, I gave up. If I ever need to do rotated EOFs I’ll probably need to write my own rotation algorithm.
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From Inel: Please tell me how you would answer Beverley’s comment … Original item in italics.

We are watching the arctic and antarctic melting.
Since the northern hemisphere is now entering winter, the arctic is freezing. But the long term trends has been a decline in sea ice. However, there has been no corresponding loss of sea ice in the antarctic, see the current southern hemisphere sea ice anomaly. For what it’s worth, the loss of sea ice does not affect sea level.

We are experiencing big changes in our weather, flooding[,] hotter and longer summers, fires where they never were before due to droughts.
See below.

We seem afraid to say the dirty word, “global warming” when this “different” weather is being described.
And naturally so! From realclimate, “is that there is no way to prove that [a single weather event] either was, or was not, affected by global warming. For a single event, regardless of how extreme, such attribution is fundamentally impossible. We only have one Earth, and it will follow only one of an infinite number of possible weather sequences. It is impossible to know whether or not this event would have taken place if we had not increased the concentration of greenhouse gases in the atmosphere as much as we have. Weather events will always result from a combination of deterministic factors (including greenhouse gas forcing or slow natural climate cycles) and stochastic factors (pure chance).”

I get mail and e-mail pleading for money to “Save the Polar Bears”.
Send your money if you want. But I get e-mail pleading for money to enlarge my penis too.

Can anyone tell me HOW, in real life[,] that can be accomplished?
I’m assuming you mean “saving the polar bears” right? I don’t know. But I assume lowering the global temperature would be a good start.

We not only CANNOT suddenly stop driving our gasoline powered cars and CAN’T suddenly convert the world to non-polluting industries.
I reject your premise. See what California did with the electric car. 100% electric cars were made and driven OVER 10 YEARS AGO! Actually, electric cars were around before the gasoline car, but that’s a different story. We can stop driving gasoline powered cars. Industry does not have to pollute the environment. A defeatist attitude won’t accomplish anything.

We are and have been further delayed due to “big business” and government interests which deal in their short term interests rather than long term which might “jeopardize the economy” (Bush’s words, I believe!).
Sure. But so what? Big Business has always favored the status quo. Business will adapt so that they make the most money.

When you face the facts, we are doomed to creating more carbon dioxide as humans can’t, haven’t and won’t eliminate the problem of global warming in time.
Predicting the future based on your ‘gut’ feelings isn’t very scientific. I’m inclined to simply dismiss this comment unless you can offer some sort of citation.

The polar bears are without a single doubt, doomed.
Maybe. Polar bears aren’t my thing. But USGS says that “[f]uture loss of Arctic sea ice could result in a loss of 2/3 of the world’s polar bears within 50 years.” My thoughts: polar bears are just one species that is threatened by climate change. By continuing to emphasize the loss of one species, we are ignoring the many other species that face extinction due to global climate change.

There is no way that we can suddenly reverse the effects of global warming
Yes there is! Even according the James Hansen there is still time to act. Hansen is probably the most outspoken scientist with respect to climate change, and is labeled by many as alarmist. The planet is warming, but the consequences from this warming can be minimized according to Hansen.

We have absolutely no way to stop the ice at the poles from melting.
Sure we do. See link above.

In time Florida and all low lying coastal areas world wide WILL be under water.
They most certainly will. But what is the time scale? The mean sea level is rising by roughly 3 millimeters (one tenth of an inch) per year (realclimate). If the rate of sea level rise continues, after 100 years it will be 0.3 meters (1 foot) higher than it is now. During the last interglacial period, the estimated sea level rise was 10 millimeters per year (ibid., and Overpeck et al.). In 100 years, this would produce a sea level rise of 1 meter (~3 feet). This is a huge amount, don’t get me wrong. And if the entire Greenland ice sheet melts, the amount of sea level rise will be greater. But it takes time for this to occur.

Droughts, fires, (which will and are adding still more co2 to the atmosphere), floods, hurricanes and tornadoes WILL increase.
The number of hurricanes is not projected to increase; their intensity may increase (see realclimate link above). I have not seen any studies which relate tornadoes to global warming. I have seen studies which predict droughts, fires, and floods will increase.

We ARE already experiencing the beginning effects of global warming.
The effects of global warming have been seen since about the 1980s. They were predicted much earlier than that. The fact that the public is just recognizing the fact now is a commentary on how well the media (and scientists!) report science news to the public.

We have a compounded problem here, as when land becomes more and more uninhabitable, human beings will be forced to move into the remaining shrinking inhabitable spaces.
Loss of habitat may become a problem, and is related to…

We have done nothing to reduce human population, (actually, China with “one child only” has made an attempt) so more wars are inevitable as man fights over possesion of inhabitable land.
The rapid increase in human population is a problem.

Can anyone tell me that I am wrong in my observations? I doubt it.
Yes.

Al Gore and scientists can be commended for enlightening us about global warming, but I cannot see how in reallity our poor old world can be saved.
Just because you cannot understand how something can be done to “save the world” doesn’t mean it isn’t possible. The is the same logical falacy that is used against evolution - “I don’t understand it, so it must not be true.”

It is already too late.
NO IT ISN’T! See above.

We are already in the downward spiral, global warming which will be impossible to reverse.
Same as above. NO IT ISN’T! See above.

(I am not, by nature[,] a negative person, just practical!)
From the nature of your comments above, I would disagree.

Investigation of the Summer Climate of the Contiguous United States and Mexico Using the Regional Atmospheric Modeling System (RAMS). Part II: Model Climate Variability

Abstract: Summer simulations over the contiguous United States and Mexico with the Regional Atmospheric Modeling System (RAMS) dynamically downscaling the NCEP–NCAR Reanalysis I for the period 1950– 2002 (described in Part I of the study) are evaluated with respect to the three dominant modes of global SST. Two of these modes are associated with the statistically significant, naturally occurring interannual and interdecadal variability in the Pacific. The remaining mode corresponds to the recent warming of tropical sea surface temperatures. Time-evolving teleconnections associated with Pacific SSTs delay or accelerate the evolution of the North American monsoon. At the period of maximum teleconnectivity in late June and early July, there is an opposite relationship between precipitation in the core monsoon region and the central United States. Use of a regional climate model (RCM) is essential to capture this variability because of its representation of the diurnal cycle of convective rainfall. The RCM also captures the observed long-term changes in Mexican summer rainfall and suggests that these changes are due in part to the recent increase in eastern Pacific SST off the Mexican coast. To establish the physical linkage to remote SST forcing, additional RAMS seasonal weather prediction mode simulations were performed and these results are briefly discussed. In order for RCMs to be successful in a seasonal weather prediction mode for the summer season, it is required that the GCM provide a reasonable representation of the teleconnections and have a climatology that is comparable to a global atmospheric reanalysis.

The full text is freely available at the link provided above. I’m going to extract the first two figures and ignore the rest of the paper. There are 22 pages in this paper, and the two figures are on pages 3 and 4. So there is a lot more to this paper than what I will talk about. They show the first 3 rotated EOFs (empirical orthogonal functions) as an extension of two previous papers to the global sea surface temperature data from 1950-2000.
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Influence of savanna fire on Australian monsoon season precipitation and circulation as simulated using a distributed computing environment

Abstract: Fires in the Australian savanna have been hypothesized to affect monsoon evolution, but the hypothesis is controversial and the effects have not been quantified. A distributed computing approach allows the development of a challenging experimental design that permits simultaneous variation of all fire attributes. The climate model simulations are distributed around multiple independent computer clusters in six countries, an approach that has potential for a range of other large simulation applications in the earth sciences. The experiment clarifies that savanna burning can shape the monsoon through two mechanisms. Boundary-layer circulation and large-scale convergence is intensified monotonically through increasing fire intensity and area burned. However, thresholds of fire timing and area are evident in the consequent influence on monsoon rainfall. In the optimal band of late, high intensity fires with a somewhat limited extent, it is possible for the wet season to be significantly enhanced.

This should be an interesting paper. There are actually two interesting bits: the distributed computing (which I’ve always found cool), and the influences of fire on the monsoon precipitation. I didn’t delve into the paper to understand if they think it’s the aerosols that are causing the change in precipitation, or if it’s a dynamical effect due to increased atmospheric heating, or even if it’s due to land cover changes. It would be nice if it was aerosols, because they are thought to have the effect of decreasing precipitation. However, as far as I’m aware, no GCMs can accurately parameterize the effects of aerosols on precipitation.

Darn, the thought of this being a paper on aerosols made me look a little closer. They are not looking at aerosol effects. They are only considering the forcings due to the amount of area burned, its intensity, the timing during the year, and amount of time needed to regrow the burned material. So it appears they are considering both land cover changes and heat fluxes. 2 out of 3 isn’t bad. But I would suspect that the aerosols would have a dramatic influence as well, as shown in Warner [1968] and Rosenfeld [1999], among others.

Lynch, A. H., D. Abramson, K. Gorgen, J. Beringer, and P. Uotila (2007), Influence of savanna fire on Australian monsoon season precipitation and circulation as simulated using a distributed computing environment, Geophys. Res. Lett., 34, L20801, doi:10.1029/2007GL030879

Rosenfeld, D. TRMM observed first direct evidence of smoke from forest fires inhibiting rainfall Geophys. Res. Lett., 1999, 26, 3105-3108

Warner, J. A reduction in rainfall associated with smoke from sugarcane fires—An inadvertent weather modification? J. Appl. Meteorol., 1968, 7, 247-251