>Weather noise and seasonal variability have stifled my previous attempts to animate noisy datasets like TLT anomalies. That noise made it difficult, at best, to determine what is taking place. A short example of a .gif animation of monthly TLT anomaly maps is shown in Figure 1.
Figure 1 – Sample Animation – Not Used In Video
Recently, I began animating maps that represent 12-month averages of “noisy” datasets with good results. The weather noise and seasonal variations are gone, for the most part. The 12-month-averaged TLT anomaly maps present a much “smoother” animation, as shown in the .gif sample, Figure 2.
Figure 2 – Sample Of Animation Used In Video
In the video, I liken the effect to smoothing the data in a time-series graph with a 12-month filter, Figure 3.
Figure 3 – Smoothed Time-Series Graph
The following 2-part video series provides detailed descriptions, time-series graphs, and animations of the processes that take place during El Niño and La Niña events. It uses TLT, SST, Total Cloud Amount, Sea Level, and Downward Shortwave Radiation anomalies to help illustrate the significant differences between the 1997/98 El Niño and the 1998/99/00/01 La Niña.
The videos also help illustrate why the effects of ENSO cannot be removed from the global surface temperature record by simply subtracting scaled and lagged NINO3.4 SST anomalies (or another ENSO index) from global temperature anomalies. There are significant residuals that contribute to global temperature anomaly trends, and these residuals are not accounted for with the simple methods used in climate studies such as Thompson et al (2009). Link (with paywall) to Thompson et al (2009):
I’ve also included animations that compare global SST anomalies with the other datasets. A sample frame that compares SST and TLT anomalies is shown in Figure 4. To indicate the timing of the maps as they proceed from El Niño to La Niña, many of the animations also include time-series graphs that fill in as time progresses.
Figure 4 – Sample Frame From Animation Of Two Datasets
Please view the animations full screen and, if possible, in high definition.
SOURCES AND DATASETS
The maps were created using the map-making feature of the KNMI Climate Explorer, which was also used for the data in the time-series graphs.
The primary SST and SST anomaly data used in the animations and graphs are NOAA/Reynolds Optimum Interpolation (OI.v2) SST.
For the comparison to tropical Pacific Ocean Heat Content, a longer-term SST dataset was required, and for that graph, I used Kaplan/Reynolds (OI.v2) NINO3.4 SST anomalies from the Monthly climate indices webpage of the KNMI Climate Explorer. Link to Kaplan overview:
The other datasets used in the videos are also available through the KNMI Climate Explorer and they include:
1. International Satellite Cloud Climatology Project (ISCCP) Total Cloud Amount data. Link:
2. CAMS-OPI [Climate Anomaly Monitoring System ("CAMS") and OLR Precipitation Index ("OPI")] precipitation data. Link:
3. RSS MSU Lower Troposphere Temperature (TLT) anomalies. Link:
4. CLS (AVISO) Sea Level anomalies. Link:
5. NCEP/DOE Reanalysis-2 Surface Downward Shortwave Radiation Flux (dswrfsfc) anomalies. Link:
There is also an animation of the Equatorial Subsurface Temperature Cross-sections that are available through the ECMWF website:
The Trade Wind Index (5S-5N, 135W-180) Anomaly data is available through the NOAA CPC website. Scroll down to the second grouping for the anomaly data:
The first detailed posts on the multiyear aftereffects of El Nino events are:
Can El Nino Events Explain All of the Global Warming Since 1976? – Part 1
Can El Nino Events Explain All of the Global Warming Since 1976? – Part 2
Supplement To “Can El Nino Events Explain All Of The Warming Since 1976?”
Supplement 2 To “Can El Nino Events Explain All Of The Warming Since 1976?”
The impacts of these El Nino events on the North Atlantic are discussed in:
There Are Also El Nino-Induced Step Changes In The North Atlantic
Atlantic Meridional Overturning Circulation Data
The Lower Troposphere Temperature (TLT) anomaly responses are discussed in:
RSS MSU TLT Time-Latitude Plots… Show Climate Responses That Cannot Be Easily Illustrated With Time-Series Graphs Alone
El Ninos Create Step Changes in TLT of the Northern Hemisphere Mid Latitudes
The misrepresentation of ENSO in climate studies are discussed in the following (The discussions are similar but there are differences in the presentation):
Climate Studies Misrepresent The Effects Of El Nino And La Nina Events
The Relationship Between ENSO And Global Surface Temperature Is Not Linear
Multiple Wrongs Don’t Make A Right, Especially When It Comes To Determining The Impacts Of ENSO
Regression Analyses Do Not Capture The Multiyear Aftereffects Of Significant El Nino Events.”
Posts related to the effects of ENSO on Ocean Heat Content are here:
ENSO Dominates NODC Ocean Heat Content (0-700 Meters) Data
North Atlantic Ocean Heat Content (0-700 Meters) Is Governed By Natural Variables
North Pacific Ocean Heat Content Shift In The Late 1980s
Detailed technical discussions can be found here:
More Detail On The Multiyear Aftereffects Of ENSO – Part 1 – El Nino Events Warm The Oceans
More Detail On The Multiyear Aftereffects Of ENSO – Part 2 – La Nina Events Recharge The Heat Released By El Nino Events AND…During Major Traditional ENSO Events, Warm Water Is Redistributed Via Ocean Currents.
More Detail On The Multiyear Aftereffects Of ENSO – Part 3 – East Indian & West Pacific Oceans Can Warm In Response To Both El Nino & La Nina Events