The Impact of Sandy on Sea Surface Temperature Anomalies Along Its Track
Guest post by Bob Tisdale
We’ve established in recent posts that, based on linear trends, the sea surface temperature anomalies along Sandy’s storm track haven’t risen in 70+ years and that there was nothing unusual about the sea surface temperature anomalies there during October 2012. And we’ve established and discussed for years that there is no anthropogenic global warming component in the warming of global sea surface temperatures or ocean heat content.
Yet activist websites continue to post climate change alarmist nonsense in Sandy’s wake. See examples here, here and here. And they call themselves realists. They must think Salvador Dali’s paintings were realistic. Refer to the discussion of Dali’s The Persistence of Memory. MOMA notes that “Dalí painted this work…he said, ‘to systematize confusion and thus to help discredit completely the world of reality.’” I read that and instantly thought of Joe Romm at ClimateProgress and John Cook at SkepticalScience.
I’m tired of responding to their drivel, so this is an informative post.
It presents the impacts of Sandy on the sea surface temperature anomalies, using the storm track data for the week centered on Wednesday October 24th, which, due to data availablity, we’ll have to consider the week during Sandy, and the week of October 31st, which will be the week after.
Like El Niño events, tropical cyclones (hurricanes) are one of Mother Nature’s ways of transporting heat from the tropical oceans toward the poles. These processes allow the heat to be radiated into space more readily at higher latitudes and they also help to reduce the temperature differences between the tropics and the poles that would exist without them. Sandy was a prime example of those processes at work. It drew enough heat from the western North Atlantic to cool the sea surface temperature anomalies about 1.0 deg C along the storm track (12N-40N, 80W-70W). See Figure 1. Sea surface temperature anomalies were near their seasonal high the week of October 24th (during the storm). A week later, the week of October 31st(after the storm) they were about 1.0 deg C cooler.
Keep in mind, though, that the storm track is a reasonably small portion of the global oceans. As such, weekly sea surface temperature anomalies there can be very volatile. Figure 2 illustrates the weekly change in sea surface temperature anomalies (Week “n” Minus the Week before “n”) since the start of this portion of the weekly Reynolds OI.v2 data, January 3, 1990. As shown, weekly changes of 0.4 deg C occur regularly. Even changes of near 0.6 deg C have occurred 4 times. The drop in response to Sandy, however, was freakish—the combined aftereffects of a number of factors that contributed to the storm—and obviously not part of some new normal.
The greatest drop in sea surface temperature anomalies occurred in the extratropics, Figure 3. This should be after Sandy merged with the cold front and became a large extratropical (baroclinic) cyclone (with a small hurricane in the center?).
The Sea Surface Temperature anomaly data used in this post is available through the NOAA NOMADS website: