NOAA issued an El Niño watch yesterday morning. The watch seems a bit premature. A “watch” in NOAA parlance means “conditions are favorable,” but the synopsis of the NOAA report reads:
There is a 50% chance that El Niño conditions will develop during the second half of 2012.
A 50% chance also means that El Niño Southern Oscillation (ENSO)-neutral conditions (not an El Niño and not a La Niña) are just as likely. Seems to me, an El Niño watch would have been more appropriate when the odds are weighted a little more toward El Niño. That may happen next month…and it may not.
Within hours of NOAA issuing the watch, Joe Romm of Climate Progress published the blog post NOAA Says ’50% Chance’ El Niño Will Develop In Second Half Of 2012, Which NASA Says Would Lead To ‘Rapid Warming’. The majority of Romm’s post is a parroting of the contents of the January 12, 2012 GISS webpage Global Temperature in 2011, Trends, and Prospects.
Let’s look at the source of the “rapid warming” in Joe Romm’s title.
NASA explains that the apparent recent slowdown in global surface temperature rise is likely to prove “illusory”:
And he quotes from GISS (his boldface):
The cool La Niña phase of the cyclically variable Southern Oscillation of tropical temperatures has been dominant in the past three years, and the deepest solar minimum in the period of satellite data occurred over the past half dozen years. We conclude that the slowdown of warming is likely to prove illusory, with more rapid warming appearing over the next few years.
The paragraph of the GISS document that Joe Romm quoted in part from was the summary of the 2011 GISS report. It reads in full:
2011 was only the ninth warmest year in the GISS analysis of global temperature change, yet nine of the ten warmest years in the instrumental record (since 1880) have occurred in the 21st century. The past year has been cooled by a moderately strong La Niña. The 5-year (60-month) running mean global temperature hints at a slowdown in the global warming rate during the past few years. However, the cool La Niña phase of the cyclically variable Southern Oscillation of tropical temperatures has been dominant in the past three years, and the deepest solar minimum in the period of satellite data occurred over the past half dozen years. We conclude that the slowdown of warming is likely to prove illusory, with more rapid warming appearing over the next few years.
It appears Romm forgot to include an ellipse and a bracket on his upper-case “T” at the beginning of his quote to indicate he was not presenting that sentence in full. The complete sentence starts with the word “However”, which might lead readers to investigate what was written before it. The sentence that comes immediately before the Romm quote reads:
The 5-year (60-month) running mean global temperature hints at a slowdown in the global warming rate during the past few years.
A 5-year running mean of GISS Land-Ocean Temperature Index (LOTI) data does more than hint at a slowdown global in the global warming rate, it shows it quite well. Refer to the GISS Figure 3. The 5-year average (centered on the 3rdyear) in 2009 is the same as it was in 2003 (0.53 deg C). Not too surprisingly, Joe Romm chose to exclude any reference to that in his quote. What did surprise me was the sentence that Romm did include (my boldface):
However, the cool La Niña phase of the cyclically variable Southern Oscillation of tropical temperatures has been dominant in the past three years, and the deepest solar minimum in the period of satellite data occurred over the past half dozen years.
GISS has stated that global surface temperatures have flattened, in part, because La Niña conditions dominated the last three years. Based on GISS Land-Ocean Temperature data, the 2009-2011 average NINO3.4 sea surface temperature anomalies (the ENSO index referred to by GISS in their report) was -0.19 deg C, and that confirms that La Niña has dominated the past 3 years. But the GISS statement also implies the opposite occurs when El Niño events dominate ENSO.
It just so happens, I’ve been illustrating that fact for the past year and a half. It began with my post Multidecadal Changes In Sea Surface Temperature. The alternate title reads Do Multidecadal Changes In The Strength And Frequency Of El Niño and La Niña Events Cause Global Sea Surface Temperature Anomalies To Rise And Fall Over Multidecadal Periods? The WattsUpWithThat cross post ishere.
I also discuss this in the Introduction of my upcoming ebook The Ignored Driver of Global Climate: El Niño-Southern Oscillation.
During a multidecadal period when El Niño events dominate (a period when El Niño events are stronger, when they occur more often and when they last longer than La Niña events), more heat than normal is released from the tropical Pacific and more warm water than normal is transported by ocean currents toward the poles—with that warm water releasing heat to the atmosphere along the way. As a result, global sea surface and land surface temperatures warm during multidecadal periods when El Niño events dominate. Similarly, global temperatures cool during multidecadal periods when La Niña events are stronger, last longer and occur more often than El Niño events.
I discussed it in much more detail in my book If the IPCC was Selling Manmade Global Warming as a Product, Would the FTC Stop their deceptive Ads? And since I haven’t reached that far in the draft of The Ignored Driver of Global Climate: El Niño-Southern Oscillation, I’ll have to quote from my existing book:
There are multidecadal periods, however, during the 20th Century when El Niño events are stronger and more frequent than La Niña events. We can illustrate this using the average NINO3.4 sea surface temperature anomalies for given periods. For our example, we’ll use the early and late 20th Century warming periods, and the mid-century “flat temperature” period. We’ll extend the late warming period to 2010 to bring it more up to date. And we’ll compare annual NINO3.4 data to GISS Global Land-Ocean Temperature Index (LOTI) data. See Figure 6-50. The period-average NINO3.4 sea surface temperature anomalies during the early and late warming periods are quite similar. On the other hand, the period average NINO3.4 sea surface temperature anomalies during the mid-20th Century flat temperature period are slightly negative.
In Figure 6-51, the temperature scale of the graph has been reduced so that it better shows the global surface temperature and the period-average NINO3.4 sea surface temperatures.
For the early warming period of 1917 to 1944, the average NINO3.4 sea surface temperature anomalies are about +0.175 deg C, and during the late warming period of 1977 to 2010, they’re approximately +0.188 deg C. The fact that the average NINO3.4 sea surface temperature anomalies are greater than zero indicates that the frequency and magnitude of El Niño events are greater than La Niña events. That would also indicate, during those periods:
1. more warm water is released from the Pacific Warm Pool than “normal”,
2. the tropical Pacific is releasing more heat than normal into the atmosphere,
3. teleconnections are causing surface temperatures outside of the tropical Pacific to warm more than normal, and
4. more warm water than normal is being redistributed toward the poles.
Suppose instead of the large periodic events, there were long-term low-temperature El Niño events taking place during those two periods; that is, one long El Niño during each warming period; we would expect surface temperatures to rise. And that is, in effect, what happened.
The reverse should happen during multidecadal periods when NINO3.4 surface temperatures are below normal. The average NINO3.4 sea surface temperature anomalies for the period of 1944 to 1976 is -0.05 deg C. La Niña events obviously dominated the mid-20th Century “flat temperature” period. And since La Niña events dominated:
1. less warm water is released from the Pacific Warm Pool than “normal”,
2. the tropical Pacific is releasing less heat than normal into the atmosphere,
3. teleconnections are causing surface temperatures outside of the tropical Pacific to warm less than normal, and
4. less warm water than normal is being redistributed toward the poles.
So we would expect Global land plus sea surface temperatures to decline during that period. And using GISS Land-Ocean Temperature Index data, that’s exactly what happened during that period. Refer to Figure 6-52.
Joe Romm closed his post yesterday with:
Stay tuned. The heat is on.
Apparently, Joe hasn’t realized the heat’s been on since 1976 when El Niño events started to dominate ENSO.
Maybe, just maybe, we’ve recently entered into a new epoch when the frequency, magnitude and duration of La Niña events exceed those of El Niño. In other words, has El Niño turned over control of ENSO to his little sister La Niña? Only time will tell.