Let us repeat together: localised weather does not equal global climate conditions.
Extreme weather events of increasing magnitude and frequency, almost all of which have been predicted by climate change models, however are climactic.
A record heat wave in Australia, with Sydney experiencing its hottest day in nearly 80 years might embolden those who are trying to get decisive action on global warming, but the inversely extreme cold temperatures and conditions experienced in the continental Unite States is bringing out a lot of unhinged scepticism.
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The Union of Concerned Scientists puts the localised American Freeze in context:
The total area of the US, including Alaska and Hawaii, is only about 2 percent of the surface area of Earth. This map from the University of Maine Climate Change Institute showing the deviations from average temperature for this time of year demonstrates this concept well—much of the continental US may be unusually cold right now but most of the rest of the world is well above average (Figure 1).
Alaska has been unusually warm this winter even though it is in the Arctic. It might seem strange that local weather events such as a balmy Alaska and freezing Florida can occur at the same time, but they’re examples of another phenomenon we can expect from a changing climate: more events at the extremes.
This is becoming better understood due to more inquiry and research into climate change. It comes from the basic notion that more heat in the atmosphere can increase the severity of weather events. Storms become more severe, and shifts in weather patterns more intense at any time of year. This means more extremes in temperatures, rainfall, and wind.
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This has been clearly observed across the globe in rising maximumtemperatures.
An analysis of records from NASA’s Aqua satellite between 2003 and 2014 shows that spikes in maximum surface temperatures occurred in the tropical forests of Africa and South America and across much of Europe and Asia in 2010 and in Greenland in 2012. The higher temperature extremes coincided with disruptions that affected millions of people: severe droughts in the tropics and heat waves across much of the northern hemisphere. Maximum temperature extremes were also associated with widespread melting of the Greenland ice sheet.
“As anyone who pays attention to the weather knows, the Earth’s temperature has incredible variability,” said David Mildrexler from the College of Forestry at Oregon State. But across the globe and over time, the planet’s profile of high temperatures tends to be fairly stable from year to year. In fact, he said, the Earth has a maximum temperature profile that is unique, since it is strongly influenced by the presence of life and the overall frequency and distribution of the world’s biomes. It was the discovery of a consistent year-to-year profile that allowed the researchers to move beyond a previous analysis, in which they identified the hottest spots on Earth, to the development of a new global-change indicator that uses the entire planet’s maximum land surface temperatures.
In their analysis, the scientists mapped major changes in 8-day maximum land surface temperatures over the course of the year and examined the ability of such changes to detect heat waves and droughts, melting ice sheets and tropical forest disturbance. In each case, they found significant temperature deviations during years in which disturbances occurred. For example, heat waves were particularly severe, droughts were extensive in tropical forests, and melting of the Greenland ice sheet accelerated in association with shifts in the 8-day maximum temperature.
In 2010, for example, one-fifth of the global land area experienced extreme maximum temperature anomalies that coincided with heat waves and droughts in Canada, the United States, Northern Europe, Russia, Kazakhstan, Mongolia and China and unprecedented droughts in tropical rainforests. These events were accompanied by reductions in ecosystem productivity, the researchers wrote, in addition to wildfires, air pollution and agricultural losses.
“The maximum surface temperature profile is a fundamental characteristic of the Earth system, and these temperatures can tell us a lot about changes to the globe,” said Mildrexler. “It’s clear that the bulk shifts we’re seeing in these maximum temperatures are correlated with major changes to the biosphere. With global temperatures projected to continue rising, tracking shifts in maximum temperature patterns and the consequences to Earth’s ecosystems every year globally is potentially an important new means of monitoring biospheric change.”
Get used to the severely hot summers and potentially very cold winters in the years ahead. The only upside to this research is that forecasting extreme weather events is getting better, allowing for some short term precautionary measures.
The long term solution to climate change remains stuck due to those who mistake weather for climate. Or money and power for not worrying about their children’s future.
