It occurred to me as I was writing Who Turned on the Heat? – The Unsuspected Global Warming Culprit, El Niño-Southern Oscillation that I would need to provide a location for the animations when I eventually, if I eventually, published a Kindle edition. I’m assuming the links to the animations wouldn’t work in the standard Kindle reader as they do for PC and Mac versions or handheld devices with internet access.
The following are portions of the text (the complete paragraphs) that include animation links. They’re listed by chapter. If, in those paragraphs, there were also illustrations referenced and shown in the book, those illustrations were not reproduced here. Refer to the links included herein under the heading of Section 6 if you’d also like to see those illustrations.
Many of the animations have appeared here at Climate Observations in past posts, or as part of my series of YouTube videos, or were included in my first book.
I’m still editing Who Turned on the Heat? – The Unsuspected Global Warming Culprit, El Niño-Southern Oscillation, so the text in the published book may vary slightly from what’s provided here.
3.5 The Transition from ENSO-Neutral to El Niño
A couple of years ago, I used those maps of the tropical Pacific Ocean currents to create a series of animations that I presented on YouTube. The animations capture the strengthening of the Equatorial Countercurrent during the transition from ENSO-neutral phase to the 1997/98 El Niño phase and its subsequent weakening as the El Niño event transitions back toward ENSO-neutral. Because there are multiple animations showing different portions of the tropical Pacific, I’ll refer you to the post Equatorial Currents Before, During, and After The 1997/98 El Niño.
CHAPTER 3.7 The Transition from El Niño to ENSO Neutral
The Rossby wave can be seen in the first 10 to 15 seconds of the YouTube video titled Impact of the 1998 through 2001 La Niña on Sea Level Residuals. It is a cropped version of the Jet Propulsion Laboratory animation “tpglobal.mpeg”, which used to be available through the JPL Ocean Surface Topography from Space website. Unfortunately, JPL has since removed it from their Video Gallery. The slow-moving Rossby wave can also be seen in Animation 3-1. It is a gif animation created from screen captures from the JPL animation discussed above. In the Animation 3-1, I’ve limited the period to 1998.
If you allow the YouTube video to play through, you will note that there are no comparably sized Rossby waves carrying cool waters back to the western tropical Pacific at 5N-10N after the 1998/99/00/01 La Niña.
To confirm this basic difference between El Niño and La Niña events, refer to the full YouTube version of the JPL animation “tpglobal.mpeg”, which runs from 1992 to 2002. There are also no comparably-sized Rossby waves carrying cool waters back to the western tropical Pacific at 5N-10N or at 10S-5S after any La Niña event. This is further illustrated in Chapter 4.9 – An Introduction to the Delayed Oscillator Mechanism.
CHAPTER 4.8 Subsurface Temperature and Temperature Anomaly Variations in the Equatorial Pacific And an Introduction to Kelvin Waves
Animation 4-1is the full-sized version. The warm (downwelling) Kelvin wave takes place during 1997 when the warm anomalies, shown with contours of yellows and oranges, shift east. Afterwards, the cool (upwelling) Kelvin wave can be seen in 1998 when the cooler subsurface waters, shown in blues and greens, travel east. The animation continues through December 2001 to capture the rest of the 1998/99/00/01 La Niña. Note how the warm anomalies in the west continue to increase over the term of the La Niña. As a reminder, that recharging is caused by the increase in visible sunlight that’s allowed to warm the ocean, which is caused by the stronger-than-normal La Niña trade winds reducing cloud cover. (You might find your eyes drawn to the upper, anomaly portion of the animation. The lower animation is very revealing near the beginning, during the El Niño and the evolution of the La Niña.)
Just in case your browser does not automatically reduce the size of the animation after downloading, I’ve prepared a Half-Sized Version of Animation 4-1so that top and bottom parts cells will be visible on your screen. Unfortunately, much of the clarity was lost when the images were reduced in size.
Animation 4-2 is another .gif animation and it presents satellite-based maps of the sea level anomalies for the global oceans. Like Animation 3-1, it was created from screen captures taken from the JPL animation “tpglobal.mpeg”. Refer also to the complete JPL animation “tpglobal.mpeg” available on YouTube as full YouTube version of the JPL animation “tpglobal.mpeg”. Animation 4-2 starts in mid-December 1996 to capture the first of two warm (downwelling) Kelvin waves. The weaker first Kelvin wave starts at the end of December 1996 and reaches the coast of South America by February 1997. Apparently, it wasn’t strong enough to kick off the El Niño. A month later in March 1997, however, the second, much-stronger warm (downwelling) Kelvin waves begins, and it initiates the colossal 1997/98 El Niño.
So far you’ve seen warm (downwelling) Kelvin waves from the side and top. The cool (upwelling) Kelvin waves are a little more difficult to show. Let’s look at Animation 3-1again, concentrating on the western tropical Pacific at its start. Sea levels in the western equatorial Pacific are extremely low at the time. Part of the drop in sea level anomalies at that time is caused by the westerly winds pushing the warm water to the east, and part is caused by the lower temperatures there. Those factors have dropped sea level anomalies to heights lower than the minimum contour value on the color-coded anomaly scale. As a result, any additional variations are lost. Unfortunately, that’s what we’re looking for: the additional variation that shows the formation of the cool (upwelling) Kelvin wave.
Using another sea level dataset (AVISO CLS sea level anomaly data) and the map-making feature at the KNMI Climate Explorer, I’ve captured the cool (upwelling) Kevin wave that ended the 1997/98 El Niño and initiated the La Niña of 1998/99/00/01. See Animation 4-3. As you’ll note, the contour levels for the maps are large and they’re also heavily weighted toward the positive anomalies, which suppresses the positive anomalies. This allows us to concentrate on the negative anomalies. The animation shows maps of monthly sea level anomalies from January 1997 to December 1998. The cool (upwelling) Kelvin wave appears to start in February 1998. It then travels eastward, with the negative anomalies appearing to decrease before arriving at the coast of South America.
CHAPTER 4.9 An Introduction to the Delayed Oscillator Mechanism
Let’s refer again to Animation 3-1and to the screen caps of the Rossby wave after the 1997/98 El Niño taken from the JPL sea level animation, shown again as Figure 4-55. There’s only one Rossby wave visible, and it’s in the northern hemisphere.
For those who like animations, I’ve linked gif animations of the AVISO/CLS monthly tropical Pacific sea level anomaly maps, so that you can watch the interplay between Kelvin and Rossby waves. Unfortunately, AVISO/CLS changed their maps slightly after November 2010, so I’ve had to divide the animations into two periods. Animation 4-4 shows the maps from November 1992 to November 2010, and Animation 4-5presents the monthly sea level anomaly maps from December 2010 through May 2012.
One thing that hasn’t been mentioned yet: These oceanic Rossby waves that return warm or cool water from the eastern tropical Pacific are taking place primarily below the surface. This is why they’re being presented with sea level maps. A couple of years ago I prepared an animation that placed the AVISO/CLS sea level anomaly maps side-by-side with sea surface temperature anomaly maps that are also available from that web page. I’ve presented it here as Animation 4-6. I have found little evidence of those Rossby waves in the sea surface temperature data, but they are easily visible in the sea level anomaly maps.
Section 6 – Discussions of and Links to ENSO-Related Animations – Two Chapters Repeated from My First Book
This is the portion of the post where I have excluded the illustrations that appear in the book. The text and links to the same animations can also be found in the two-part blog post 1997/98 El Niño through 1998/99/00/01 La Niña Animations Part 1 and Part 2.
I’ve changed the Figure numbering and altered some of the wording.
CHAPTER 6.1 Introduction to the Animation Illustrating the Warming of the East Indian-West Pacific Sea Surface Temperatures in Response to the 1997/98 El Niño AND the 1998/99/00/01 La Niña
Animation 6-1 shows the impact of the 1997/98 El Niño and the 1998/99/00/01 La Niña on the sea surface temperature anomalies of the East Indian and West Pacific Oceans. The East Indian-West Pacific sea surface temperature anomaly data in the graph are for the coordinates of 60S-65N, 80E-180. As a reminder, as illustrated in Figure 5-20, the East Indian-West Pacific data is the primary source of the variations in the South Atlantic-Indian-West Pacific data. This was discussed in Chapter 5.5 The ENSO-Caused Upward Shifts Still Exist if We Add the South Atlantic and West Indian Sea Surface Temperature Data to the East Indian and West Pacific, and as you’ll recall, the South Atlantic-Indian-West Pacific dataset represents more than half of the surface area of the global oceans.
CHAPTER 6-2 – More ENSO Animations
Animation 6-2: Total Cloud Amount Anomalies
Figure 6-8 shows a cell from Animation 6-2, which compares sea surface temperature anomalies to total cloud amount anomalies. The total cloud amount anomalies are based on the ISCCP Cloud Amount data. ISCCP stands for International Satellite Cloud Climatology Project. Note the inverted funnel shape over the Indian Ocean in the cloud amount data (lower map). That’s from a satellite blind spot in early years that impacts the anomalies. Because our focal point is the tropical Pacific, that problem in the Indian Ocean data is not a concern. To view the animation, click here.
Animation 6-3: Precipitation anomalies
Animation 6-3 presents sea surface temperature anomalies with Climate Anomaly Monitoring System (CAMS) – OLR Precipitation Index (OPI) (CAMS-OPI) precipitation anomalies. Figure 6-9 is a sample cell. To view the animation, click here.
Animation 6-4: Sea level anomalies
Figure 6-10 is a sample cell from Animation 6-4 which compares Reynolds OI.v2 sea surface temperature anomalies to an early version of the AVISO CLSsea level anomaly data. Note that the sea level anomaly map in Figure 6-10 captures the formation of the warm (downwelling) Rossby wave at the end of the 1997/98 El Niño. Click hereto view Animation 6-4.
Animation 6-5: Pacific Ocean sea surface temperatures (not anomalies)
Sea surface temperature anomalies are compared to Pacific Ocean sea surface temperatures (not anomalies) in Animation 6-5. Figure 6-11 is a sample cell. To view the animation, click here.
Animation 6-6: Lower troposphere temperature (TLT) anomalies
Figure 6-12 is a sample cell from the last of the comparison animations. Animation 6-6 presents sea surface temperature anomalies versus Remote Sensing Systems (RSS) lower troposphere temperature (TLT) anomalies. It’s one of my favorite animations. Note how long it takes for the lower troposphere temperature anomalies in the eastern tropical to respond to the warming of the sea surface temperature anomalies and how different the spatial patterns are. Click hereto view animation 6-6.
Animation 6-7: Global with North Atlantic Graph
The first of the North Atlantic sea surface temperature animations is Animation 6-7. A sample cell is shown in Figure 6-13. With the exception of the graph and the opening few cells which highlight the location of the North Atlantic data, the maps are the same as Animation 6-1. The graph is different. It includes North Atlantic sea surface temperature anomaly data for the coordinates of 0-70N, 80W-0. To view the animation, click here.
Animation 6-8: North Atlantic and Corresponding Graph
Animation 6-8 presents only maps of the North Atlantic. See the sample cell in Figure 6-14. Click hereto view Animation 6-8.
CHAPTER 7.10 Failed Argument – The East Indian-West Pacific and East Pacific Sea Surface Temperature Datasets are Inversely Related. That Is, There’s a Seesaw Effect. One Warms, the Other Cools. They Counteract One Another.
This argument has been tried more than once. It’s typically voiced when I present a gif animation that shows the East Pacific warming and cooling in response to ENSO and shows the East Indian-West Pacific sea surface temperatures varying in the opposite direction. See Animation 7-1. The argument is, the seesaw effect between the East Pacific and the East Indian-West Pacific datasets—better described as their opposing warming and cooling—causes the two datasets to counteract one another. The argument is intended to downplay the importance of the variation in the sea surface temperatures of the East Indian-West Pacific subset.
CHAPTER 8.19 Are there Other Ways to Show that ENSO Causes the Long-Term Trends in Global Sea Surface Temperatures?
The animation and its implications are explained in detail in the post Multidecadal Changes In Sea Surface Temperature. See the YouTube video Multidecadal Changes In SST Anomalies (Blog Version).There is also a longer stand-alone version of the video: Multidecadal Changes In Sea Surface Temperature Anomalies.wmv. It runs about 5 minutes longer.