Category Archives: Climate
The cooldown that we enjoyed over the weekend, after the prolonged warm and humid spell that began September, got us thinking about the inevitable first morning with a temperature below 32 degrees.
We are less than two weeks away from the autumnal equinox, the last day until late March on which the day is at least as long as the night. Continue reading
The average global temperature of July set highs — it was the warmest month on record since record keeping began in 1880.
The observed ocean surface temperature was the highest for any month in the 1880-2015 record period. The average temperatures over land were also above the average for the 20th century, ranking as the sixth-warmest July since 1880. Continue reading
The observational evidence that the Earth is warming is overwhelming and unmistakable.
Surface observations of temperature over land and ocean have shown that all but one of the 15 warmest years on record have occurred since 2000. the average length of the ice season on a collection of widely distributed Northern Hemisphere lakes, each with at least 150 years of continuous record, has decreased by over two weeks. The areal extent of the Northern Hemisphere’s wintertime cold pool has systematically shrunk in the last two winters recording the smallest seasonal average cold pool areas since records began in 1948-1949. Continue reading
There are some spectacular photographs and videos of the recent eruption of Calbuco in Chile. The impact of the eruption on our weather and climate depends on how explosive the eruption and how much sulfur dioxide is in the volcanic plume.
Eruptions can lead to cooler temperatures in the mountain’s vicinity. As the ash cloud enshrouds nearby regions, it will reduce the amount of solar energy reaching the surface and thereby reduce the daytime temperatures. Continue reading
Permafrost is ground that is frozen for at least two years. It remains frozen all year and contains plant material that has not yet completely decomposed.
Permafrost is mostly located in polar regions, though it also occurs in some high mountain tops where it is called alpine permafrost. There is no permafrost in Madison, though our ground does freeze in most winters. Continue reading