Four weeks of climate data: Southern Tropics Temperature Recap

As a general rule, it would be fair to say that the most extreme warming is happening in the Arctic Circle and Western Antarctica. The Western Antarctic warm zone doesn't seem to be radiating out much heat to nearby areas, which is not surprising when you see how far away anything "nearby the Antarctic really is and when you consider the harsh seas and skies that surround the South Pole.

The Southern Tropics have no slice that gets near our somewhat arbitrary level of 1° C rise in temperature over the 56 year period we have chosen to look at, based on Strong La Niña currents.

Tomorrow, our last region, the southern temperate zone, with even more water and less land mass than the southern tropics.

Four weeks of climate data: Southern Tropics Region #6

 The last slice of the Southern tropics is all in the Atlantic Ocean between South America and Africa.

One station reported enough to be noticed from 1955 to 2010. This is the island of Ascension.

Notice there are gaps in the record in the first era from 1955 to 1975. Even so, there is enough data to be used under my system.

This is a region much like the rest of the Southern tropics.

If there is one difference, it's Winter. The median from 1999 to 2010 is slightly lower than the median from 1955 to 1975. It's anyone's guess if this would still be true if the missing years in the 1950s and 1960s existed.
 

Here's the overall story.

Confidence of the region warming: 99.5%
Confidence of increasing rate: 89%
Change in median temperature from the 1955-1975 interval to the 1999-2010 interval: 0.37° C


The Southern Tropics have some variation, but the basic story is we are confident of the warming, not confident of an increasing rate and the difference in the median values from the first era to the last are all well below a degree C.


Tomorrow, we start out look at the last section of the globe, the Southern Temperate Zone, which has even less land mass than the Southern Tropics.

Four weeks of climate data: Southern Tropics Region #5

 One of the main reasons I made the slices of the Southern Tropics different widths was to make sure one slice covered all of the land mass of South America that lies inside this region.

As you can see, there are some grid points in the Amazon basin that aren't covered in the era of 1955 to 2010, but overall the coverage is strong.

The low temperature graph of the Summer data shows steady warming, but barely a half degree. The other measurement bounce around a little, but they also show mild warming.

Again, generally warming but only slightly.

In all four of the graphs, the warmest reading of these 56 years happened some time in the 1990s.

And the Spring most resemble the Winter data.

Confidence of the region warming: 97.7%
Confidence of increasing rate: 50%, could go either way which means no confidence at all
Change in median temperature from the 1955-1975 interval to the 1999-2010 interval: 0.33° C


Yet again, we have a warming region, but it is not warming by very much or is it showing signs of speeding up. Later today, the last slice of the Southern Tropics, a few islands in the tropical southern Atlantic.

Four weeks of climate data: Southern Tropics Region #4

Another region of the Southern Tropics that consists of lots of ocean and a few islands.

Even for that, the coverage is well spread out.

A generally warming trend, but the most recent jump is smaller than some previous jump in every metric.

Again increasing, but the overall median increase is less than half a degree.

Clearly increasing, but less than half a degree again.

One cool Spring this century keeps this from being a convincing warming trend in all metrics.

Confidence of the region warming: 99.99%
Confidence of decreasing rate: 65%
Change in median temperature from the 1955-1975 interval to the 1999-2010 interval: 0.48° C


Tomorrow, we will have a slice of the tropics with a lot of land mass as we look at South America south of Ecuador.

Four weeks of climate data: Southern Tropics Region #3

 This is the last of the Southern Tropics in the Eastern Hemisphere, covering Indonesia, New Guinea, the tropical part of Australia and a lot of the islands east of Australia. New Zealand is far to the south of this region, entirely contained in the Southern Temperate region.

There are reliable weather stations all over this region.

This is yet another region whose coldest and warmest average temperatures are not that far apart. The median shows a very steady increase, neither speeding up or slowing down.

The Fall median looks a lot like the Summer, showing steady increase but not growing faster or slower.

The Winter temperatures bounce around a little bit more, but the last two time intervals are definitely warmer than the first two.

Spring temperatures are definitely on the rise in all metrics, but that rise appears to be slowing down.

Confidence of the region warming: 99.9%
Confidence of increasing rate: 50%, neither speeding up or slowing down.

Change in median temperature from the 1955-1975 interval to the 1999-2010 interval: 0.55° C

Yet again, the trend is definitely warming, but the rise averages out to very close to 0.01° C a year, which is not catastrophically fast.

Later today, another slice of the tropical southern ocean with a lot more water than land.

Four weeks of climate data: Southern Tropics Region #1

The first region in the southern tropics covers sub-Saharan Africa and Madagascar. It should be noted that his is directly south of the region that showed the most warming in the norther tropics at nearly a degree Celsius in 56 years.

The reporting of stations looks to be a little spotty. The chunk where the text is should be somewhere around Angola or the Democratic Republic of Congo.

The story in the Summer and Fall are remarkably similar. The median trend is increasing as is the record low, but the rate is not getting faster.

The other thing the Summer and Fall patterns share is the record warm was in the late 1990s.

Winter and Spring are similar to each other as well and the pattern is very clearly warming, though the jumps are not getting taller as time goes by.

Confidence of the region warming: 99.9999%
Confidence of increasing rate: 50%, which means neither getting faster or slower
Change in median temperature from the 1955-1975 interval to the 1999-2010 interval: 0.70° C


Later today, a slice of the Indian Ocean with just a smattering of islands.

Four weeks of climate data:The Southern Tropics

As we move south from the Northern Temperate Zone, we get more ocean and less land mass. With the Southern Tropics, I decided not to be so arbitrary about the width of the six regions and cut this part of the world into six slices that made sense geographically. The first slice is the usual width of 60 degrees of longitude and covers Africa and Madagascar.

 

The next slice is thinner and is mostly open Indian Ocean.

The last slice of the Eastern Hemisphere is wider than usual and covers the Southern part of Indonesia, the tropical part of Australia, all of New Guinea and some of the islands east of Australia, best known to Americans as the places where the Pacific theater of World War II was fought.

The first slice of the Western Hemisphere is more open ocean, this time the South Pacific.

The second slice gives us all of South America and the Galapagos.

The last slice is open ocean in the south Atlantic.

Later today, we will look at the numbers for the first two sections.