The author of the recent SkepticalScience post Distinguishing Between Short-Term Variability and Long-Term Trends, Dana Nuccitelli, still misunderstands or misrepresents El Niño and La Niña processes. Either way, he’s missed something. The instrument temperature record indicates that La Niñas and El Niños serve as a natural recharge-discharge oscillator, with La Niñas acting as the recharge mode and El Niños serving as the discharge and distribution phase. As such, the data indicate that El Niño and La Niña events are responsible for the natural warming of global sea surface temperatures over the past 31 years and that they’re the cause of a portion of the warming of ocean heat content since 1955. If this subject is new to you, refer to my illustrated essay “The Manmade Global Warming Challenge” [42MB]. Also, we’ve discussed time and again that an El Niño-Southern Oscillation (ENSO) index only represents the impacts of ENSO on the variable being measured, and that an ENSO index does not represent all of the ENSO processes or their aftereffects, but the SkepticalScience author Dana Nuccitelli continues to present myths about ENSO indices—and, in turn, about global warming.
I have not read the recent post by Dana Nuccitelli in its entirety. Based on the opening paragraph, it looks to be a comment on the McLean et al (2009) paper Influence of the Southern Oscillation on tropospheric temperature. This post is not a defense of that paper. It’s about the closing statement of Dana Nuccitelli’s post, which is clearly a falsehood. Nuccitelli writes:
If we remove the long-term warming trends, we can see once again that the short-term wiggles in the temperature data are strongly influenced by changes in ENSO. However, the long-term global warming trends are not – they are due to the human-caused greenhouse effect.
Here’s a challenge to Dana Nuccitelli and other bloggers from SkepticalScience. You and your associates at SkepticalScience claim to have analyzed more than 12,000 peer-reviewed papers about global warming and climate change. What I present in the following should be a really easy task, because lower troposphere temperature anomalies for the mid-to-high latitudes of the Northern Hemisphere warmed in a very specific way. Surely, out of the 12,000 papers, a few of them must have addressed how lower troposphere temperatures have actually warmed.
If you believe that manmade greenhouse gases are responsible for the recent bout of global warming, please provide links to the climate model-based, peer-reviewed papers that explain:
1. How and why the lower troposphere temperature anomalies of the mid-latitudes of the Northern Hemisphere show upward shifts in response to strong El Niño events—without proportional cooling during the trailing La Niñas. That is, the RSS lower troposphere temperature anomalies for the latitudes of 20N-90N do not cool proportionally during the La Niña event of 1988/89, Figure 1, but they did warm in response to the 1986/87/88 El Niño, which caused a major portion of the long-term warming trend.
2. And how and why the RSS lower troposphere temperature anomalies for the latitudes of 20N-90N do not cool proportionally during the La Niña event of 1998-01, Figure 2, but they did warm significantly in response to the 1997/98 El Niño, which caused another major portion of the long-term trend.
It is blatantly obvious to anyone reading and comprehending those two graphs that there would be little to no long-term warming of the lower troposphere temperature anomalies for mid-to-high latitudes of the Northern Hemisphere if lower troposphere temperature anomalies had cooled proportionally during the La Niña events of 1988/89 and 1998-01.
I first discussed the warming of lower troposphere temperature data almost 4 years ago in the post RSS Time Latitude Plots Show Climate Responses That Cannot Be Easily Illustrated With Time-Series Graphs Alone. And I discussed why the lower troposphere temperature anomalies for the mid-to-high latitudes of the Northern Hemisphere do not cool proportionally during the 1988/89 and 1998-01 La Niñas in the post The ENSO-Related Variations In Kuroshio-Oyashio Extension (KOE) SST Anomalies And Their Impact On Northern Hemisphere Temperatures.
Back to Nuccitelli’s closing statement: That was the same conclusion reached in a recent video by SkepticalScience, using surface temperatures. I responded to their video with the post The Blatant Errors in the SkepticalScience Video “Global Warming over the Last 16 Years”, which includes the following YouTube video:
DON’T FORGET SEA SURFACE TEMPERATURE AND OCEAN HEAT CONTENT
Further to my challenge to Dana Nuccitelli and his associates at SkepticalScience: if you continue to believe that manmade greenhouse gases are responsible for the recent bout of global warming, please provide links to the climate model-based, peer-reviewed papers that explain how and why sea surface temperature and ocean heat content data have warmed (or not warmed) in the following ways (numbering continued from preceding section):
3. How and why the sea surface temperatures of the East Pacific (90S-90N, 180-80W) haven’t warmed in 31 years (Figure 3).
4. How and why the sea surface temperatures of the Atlantic, Indian and West Pacific Oceans (Figure 4) with the coordinate of 90S-90N, 80W-180, only warmed during the strong El Niño events of 1986/87/88, 1997/98 and 2009/10 and did not cool proportionally during the training La Niñas—and without those El Niño events, the sea surface temperatures there would show no warming.
That should be a simple task since the global oceans were only broken down into two subsets.
Moving now to ocean heat content of the tropical Pacific where the fuel for El Niño events is generated:
5. How and why the warming of the ocean heat content data for the tropical Pacific, Figure 5, is dependent on the 1973-76 and 1995/96 La Niña events, and without those La Niñas the ocean heat content for tropical Pacific would cool.
Still in the subject of ocean heat content:
6. How and why the warming of the ocean heat content of the North Pacific (north of the tropics) is dependent on a 2-year climate shift (1989-90), and without that climate shift, the ocean heat content for the North Pacific would cool (Figure 6).
I discussed the above four graphs and the natural processes that caused their warming in the illustrated essay “The Manmade Global Warming Challenge” [42MB] and in the YouTube video series “The Natural Warming of the Global Oceans” Part 1 and Part 2. And I also discussed them in great detail in my ebook Who Turned on the Heat? which is available in pdf form for only US$8.00. Who Turned on the Heat? also discusses the warming of lower troposphere temperature anomalies shown in Figures 1 and 2.
There’s no reason to wait for links to peer-reviewed papers from Dana Nuccitelli and his associates at SkepticalScience—links that will offer climate model-based explanations for how and why the oceans have warmed in the fashions they’ve warmed and how the lower troposphere temperature anomalies warmed as they had. The warming is dependent on ENSO, and for the ocean heat content of the North Pacific, it depends on a change in wind patterns and sea level pressure. The first problem they’ll encounter is trying to find studies based on climate models that can simulate ENSO. As far as I know, there are a sum total of…How should I put this?…none. See Guilyardi et al (2009), discussed in the post here.
I used the phrases “if you believe” and “if you continue to believe” as part of the challenges to SkepticalScience. Sea surface temperatures, ocean heat content and lower troposphere temperatures have all warmed in very specific ways in response to ENSO. Unless there are climate model-based peer-reviewed papers that explain specifically how and why those variables have actually warmed in the manners in which they’ve warmed as responses to ENSO, then parties like SkepticalScience who are promoting hypothetical manmade global warming are doing so based solely on their beliefs.