Four weeks of climate data: Antarctica Region #5

Yesterday evening, we looked at the fourth slice of Antarctica, or failed to look at it may be more precise. That part of the continent has the shoreline in the Ross Sea that is closest to the South Pole. The fifth slice is the part just south of Tierra Del Fuego in South America and contains most of the Antarctic Peninsula. When I was a kid, I thought Antarctica looked like a bird sitting on a nest and the peninsula was like a beak. The thick part of the beak is known as Palmer Land and the Larsen Ice Shelf is tucked in at the curve near the end of the beak on the underside. The Larsen isn't as big as some of the other shelves, but it is the northernmost.

The consistent weather stations are really measuring two grid spaces on the Peninsula. There are weather stations closer to the South Pole, but they aren't consistent over the time period we are looking at.

The record highs of Summer are not getting higher, so the top black line does not show a warming trend. In contrast, both the median and coldest temperatures are showing increase.

The Fall temperatures show the same pattern, not that the warmest season are getting warmer over time, but instead that it's not getting as cold as it used to in the coldest years and the median year is warmer than it used to be. 

Winter tells much the same story.

Only in the Spring months do we see new record high warm temperatures in this century. The coldest Spring data trends obviously up, while the median data has a big jump between the 1975-1988 time interval and the 1988-1999 data

There are 36 stair steps in our four seasons of data. 29 go up from left to right, 4 go down and 3 are too close to call. 29 of 36 is way more than half, and using the test that Sir Ronald Fisher developed for a yes/no set of data like this he first used on the experiment known as The Lady Tasting Tea, we can say with about 99.98% confidence this data shows a warming trend.

For increasing warming, we look at the consecutive steps and see if one is taller or shorter than the previous.  Here there are 24 pieces of data and our count is 15 taller, 8 shorter and 1 too close to call. 15 of 24 does not get us to the 95% confidence level (closer to 88%) so we can say it is a region showing warming, but not increasing warming. This is the first slice of the southern continent to show a warming trend. Later today, the sixth slice, which has more data reporting than any of our previous regions, including the consistent stations farthest south.