INITIAL NOTE: This post has nothing to do with the Kerry Emanuel’s new climate model-based paper, Downscaling CMIP5 climate models shows increased tropical cyclone activity over the 21st century, but feel free to comment about it. The USA Today article here about Kerry Emanuel’s paper has interviews with Judith Curry and Roger Pielke, Jr., both of whom appear a bit skeptical.
We know that climate models cannot simulate the sea surface temperature anomalies of the past 31 years. See here. So why should we have any confidence in a climate model-based study of hurricanes that depends on flawed simulations of sea surface temperatures? We shouldn’t. Also, tropical cyclones are strongly impacted by El Niño and La Niña events, and climate models still can’t simulate El Niños and La Niñas. Kerry Emanuel’s new climate model-based paper is nothing more than computer-aided speculation, using models that can’t simulate fundamental components of the study.
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NOAA announced the formation of Tropical Storm Chantal yesterday. The media reacted with headlines like USAToday’s Tropical Storm Chantal races toward Caribbean. Not to be outdone, WunderGround’s headline reads Tropical Storm Chantal: a Likely Harbinger of an Active Atlantic Hurricane Season.
This a quick look at the sea surface temperature anomalies along Chantal’s past and forecast storm track, using Reynolds OI.v2 sea surface temperature data. It was prepared in anticipation of the typical claims about the influence of global warming on tropical storms and hurricanes. I’ve divided the storm track into two regions shown in red in Figure 1. We’ll call the more southern region the Western Main Development Region. The more northern one will represent the sea surface temperature anomalies off Cuba and the East Coast of Florida. We’ll present the monthly and weekly sea surface temperature anomalies.
Figure 1
As a reminder, warm sea surface temperatures feed tropical storms, not sea surface temperature anomalies. Seasonal sea surface temperatures are obviously warm enough to sustain a tropical storm.
WESTERN MAIN DEVELOPMENT REGION
Figures 2 and 3 present the monthly and weekly sea surface temperature anomalies for the western Main Development Region. We’re using the coordinates of 10N-20N, 75W-50W. Sea surface temperatures in this region are above the base year (1971-2000) values, but they are nowhere close to the highs experienced a couple of years ago.
Figure 2
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Figure 3
OFF CUBA AND EAST COAST OF FLORIDA
Monthly and weekly sea surface temperature anomalies off Cuba and the East Coast of Florida (20N-30N, 80W-70W) are below their respective 1971-2000 averages. See Figures 4 and 5.
Figure 4
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Figure 5
NATURAL WARMING OF THE OCEANS
For four years, I’ve been illustrating and discussing how ocean heat content and satellite-era sea surface temperature data indicate the oceans warmed naturally. That doesn’t stop climate change alarmists from making all sorts of nonsensical claims. If the natural warming of the oceans is new to you, refer to the illustrated essay “The Manmade Global Warming Challenge” [42MB].
CLOSING
There’s nothing unusual about the sea surface temperature anomalies of the western Main Development Region in the North Atlantic. There is, however, something unusual about the sea surface temperature anomalies off Cuba and the east coast of Florida. In a world where we’ve been told that greenhouse gases are responsible for global warming, the sea surface temperature anomalies off Cuba and the east coast of Florida are below their 1971-2000 averages.
SOURCE
The Sea Surface Temperature anomaly data used in this post is available through the NOAA NOMADS website:
http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh
or: