Global Warming V


I confess that I have not posted Climate Change IV yet, about comparing the surface and satellite temperature measurements, but the graph below appeared along with an excellent New York Times article that reported on a recent major study and review of long term trends in sea levels. Seas Are Rising at Fastest Rate in Last 28 Centuries .

Here’s the main part of the interesting graph, which I showed to my U of Tampa students for our Science in the News discussion.

Here’s the link to this: How Much Warmer Was Your City in 2015? .

Here’s my interpretation of this data. The vertical axis is the temperature in F. The horizontal axis shows the months and days of 2015, which was the hottest year on record in the thermometer era (beginning around 1875 or 1880). The dark narrow vertical bars show the high and low temperatures for the day, in Tampa, Florida. The darker band shows the normal range of daily temperature. The fainter shades above and below the normal range show the record high and the record low for the day. Then the little triangles with annotations show any record lows or highs for the day that happened during 2015.

The temperature data for any one year or for any one place does not prove or disprove global climate change or global warming. To gather evidence for these phenomena, researchers need data from around the world and for many decades, even centuries. No one would put forward the unusual December warm spell here in Tampa to prove global warming. The data here are suggestive, however, and they reflect what the professionals gather from as many places and for as long a time span as they can.

If the climate in Tampa in 2015 were the same as the climate here had been in past, and if that climate had been stable, then in any particular year, there should be a few record lows for the day and record highs. The record low for the day, might well be on a warm summer day, and not cold at all by Boston standards. Similarly, the record high for a day might happen in the sweltering Tampa summer or in the warm cool Tampa winter. Say, 3 or 4 record lows for the day and 3 or 4 record highs.

In this chart, there is one record low for the day, in mid-February, and it looks to me to be more than two dozen record highs for the day. The highs include a hot week in early November and a memorably hot winter holiday season.

My darling wife noticed that there were several months, March and April, and November and December, when the daily temperature ranges were distincly higher than the normal ranges. There was at least one record high for the day in ten months. One of the months without a record high for the day was April, during which the temperatures were noticeably higher than the usual range.

You can find the data for Boston, Mass., here: How Much Warmer Was Your City in 2015? . In Boston last year there was one record low for the day, and three record highs. I see an unusually cold February and an unusually warm December. Perhaps March was chillier than usual, and August, September, and November were warmer than usual.

The predominance of record highs for the day over record lows for the day in Tampa suggests that the climate was warmer last year than it has been over the many years in which the temperature record highs and lows have been accumulating. It is the case, that a similar signature of excess record highs exists in the data from around the world, and going back a few decades.

This single type of evidence does not by itself prove that the world’s climate is warming, and it tells us nothing about the causes, if it is warming. The world’s climate scientists, and those in many other relevant fields, such as ecology (changing dates for migrations, for flower emergence, and so on), agronomy (changes in growing seasons, for example), epidemiology (the appearance of tropical illnesses, such as dengue fever, in temperate areas), and others, have amassed a large, impressive, and mutually consistent body of evidence that the climate is warming, and will continue to warm.

Since it has been known since the late 19th century that water vapor and carbon dioxide are what we call today greenhouse gases, and since researchers have shown that the carbon dioxide levels in the atmosphere are on their way to doubling, and more, in the past century or so, and since they can account for the source of that additional carbon dioxide in human activity, and since the 1st Law of Thermodynamics or the Conservation of Energy is super-duper strong and correct, there is no reasonable or rational doubt about anthropogenic climate change.



Filed under Climate Change, Natural Science, Science in the News

2 responses to “Global Warming V

  1. Pingback: Global Warming IV | two heads are better

  2. Pingback: Global Warming VII – Carbon Dioxide History | two heads are better

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