The NOAA report on August’s global temperatures was issued at 11 a.m. on September 20, 2016. It was already old news.
Yeah, the world’s warming. We heard that before.
Weather only impacts people’s thoughts when there’s a flood or a hurricane or a tornado. And climate?
That’s something for another generation to worry about. We have more important things on our minds.
So please excuse Decoded Science for interrupting the important things to call attention to global temperatures, which are inexorably on the rise.
August was the 16th consecutive month of record warmth for any comparable month. 14 of the 15 greatest departures from average have come in the last 14 months. Ho hum, indeed.
Many New Records Set For August
August of 2016 was warmer than normal over most of the globe, and the warmest on record (records go back to 1880) somewhere on every continent and in every ocean. The most prominent areas which established new records include:
- Most of the southern half of Africa.
- Parts of northern South America.
- The western North Atlantic Ocean, with record temperatures extending into the northeastern United States.
- Much of central China.
- Part of the South Atlantic Ocean.
- The South Pacific Ocean near South America.
- A part of western Siberia.
Below normal temperatures were confined to extreme eastern Siberia, isolated spots in the Pacific Ocean, and a spot in the Atlantic Ocean just east of the southern tip of South America. Nowhere was it record cold for the month.
The Rate Of Warming Has Slowed — A Little
With a very powerful El Niño in effect, 2015 was a blockbuster year for temperature. Normally, a powerful El Niño is followed by a robust La Niña, but the signals of this La Niña are muted. Though temperatures in the equatorial Pacific Ocean are below normal, the situation does not yet qualify as La Niña according to NOAA’s formal definition. Forecasts are now for neutral conditions to continue, with just a 30% chance of La Niña this fall or winter.
The data are broken down into nine categories: global, northern and southern hemisphere for land, sea, and combined land and sea.
For many months in late 2015 and early 2016, all nine categories set new records. August 2016 was warmest in six of the nine categories. It was second warmest (in the last 137 years) in southern hemisphere land and global ocean; and it was third in northern hemisphere ocean.
This is figuratively but not literally cold comfort for a world that is warming at a rate unprecedented except in times of climatic turmoil caused by collisions with asteroids or cataclysmic volcanic eruptions.
Northern Hemisphere Summer
Longer periods of data give a better picture of long-term trends. The northern hemisphere summer (by meteorological definition) season of June, July, and August was warmest ever over land and sea at 15.6° C (60.1° F), surpassing last year’s record by 0.04° C (0.07° F).
If we extrapolate this rate of rise, the earth will warm by 4° C (7° F) in the next hundred years. This is clearly unacceptable for those who will inherit the earth four or five generations from now.
Summer 2016 was warmest in seven of the nine categories; it was second in southern hemisphere land and northern hemisphere ocean. Looking at a longer period, the year-to-date (January through August) temperatures for 2016 were new records in every category.
The temperature for the first eight months of the year (year-to-date) exceeded the previous record set last year by 0.16° C (0.29° F). This implies a rate of increase of one degree Celsius every six years, or an increase of one degree Fahrenheit every three and one-half years.
This is almost certainly not an accurate representation of current global warming (We better hope so), since it is influenced by El Niño. Still, the temperature is clearly rising at an alarming rate, and implementation of the Paris agreement to limit greenhouse gas emissions, signed last December, cannot come too soon.
Northern Hemisphere Summer Precipitation
Though precipitation can be highly variable even between locations very close together, some trends are emerging from the summer that suggest how the climate is changing.
A swath of unusually wet weather ran from the Gulf of Mexico northward through the US. Warmer air can hold more moisture, so places in the path of a moist flow from the Gulf of Mexico will probably see increasing precipitation.
A large part of the central Eurasian land mass was very wet, as was most of Australia.
The California drought drags on, after the Pineapple Express, normally aggressive in El Niño years, produced only modest amounts of precipitation during the winter; spring and summer have been anomalously dry. Northern Africa, Southern Europe, and northern South America were also very dry.
The world is warming. If it warms at the same rate everywhere, the changes will be tolerable. But the warming is not uniform — several times the global average in the Arctic, for example. The real danger is a runaway greenhouse effect, a la Venus, where tomorrow’s forecast is for a high temperature of 500° C (900° F).