Guest Post By Bob Tisdale
The Seth Borenstein AP article about the recent high sea surface temperature…
…is misleading. There is a significant difference between what Seth Borenstein reported and what NOAA stated in the July “State of the Climate”.
Borenstein does not clarify that it is a record for the month of July, where NOAA does. NOAA writes, “The global ocean surface temperature for July 2009 was the warmest on record, 0.59°C (1.06°F) above the 20th century average of 16.4°C (61.5°F). This broke the previous July record set in 1998.” Refer to Figure 1, which is a graph of SST for July from 1982 to 2009 (NOAA’s ERSST.v3b version).
Borenstein readers are told that July 2009 Sea Surface Temperatures (SSTs) were the highest since records began, but that is false. Figure 2 illustrates monthly SSTs from November 1981 to July 2009. I’ve added a red horizontal line to show the July 2009 value.
Whether or not July SSTs represented a record is also dependent on the SST dataset. NOAA’s satellite-based Optimally Interpolated (OI,v2) dataset presents a different picture. That dataset clearly shows that July 1998, Figure 3, had a higher SST.
And looking at the monthly OI.v2 data since November 1981, Figure 4, there are numerous months with higher SSTs.
The Borenstein article also claims that Arctic SST anomalies are as high as 10 deg F (5.5 deg C) above average. Wow!! Really??
I used the SST map-making feature of the NOAA NOMADS system to create the map of high latitude Northern Hemisphere SST anomalies for July 2009. The Contour Interval was set at 1 deg C to help find the claimed excessively high SST anomalies. Alas, Borenstein was right, BUT, as you will note, the ONLY area that reaches the 5 to 6 deg C range is the White Sea (indicated by the arrow) off the Barents Sea.
And to put that in perspective, Figure 6 is the global map. Based on the Kartesh White Sea Biological Station website…
…the surface area of the White Sea is approximately 90,000 sq km. If the surface area of the Arctic Ocean is 14 million sq km, the White Sea represents less than 0.6% of it. And for those who want to compare it to the surface area of the global oceans, its surface area is 361 million sq km. Too many zeroes after the decimal point to worry about.
And the SST anomalies of one miniscule area do not represent the SST anomalies for the Arctic Ocean, as is obvious in Figure 7. Arctic SST anomalies have declined over the past few years.
SST anomaly graphs through July 2009 for the Arctic Ocean and other individual oceans can be found at my July 2009 SST Anomaly Update.
To sum up the Borenstein article, it’s factually incorrect in places, and in others, it raises alarmism to ridiculous levels by dwelling on a meaningless statistic, the July SST anomaly of the White Sea.