Sunday, 6 March 2016

A new scientific report from Dr. James Hansen

Before then, I suspect. Dr.Hansen needs to talk to a conservation biologist.

Dr. James Hansen: “We Have a Global Emergency” Dangerous Heat to Render Parts of the World Practically Uninhabitable by 2100

4 March, 2016

There’s a tragic new danger lurking in the world. Something that’s arisen from a mass burning of fossil fuels on an epic scale that now pumps out more than 100 times the greenhouse gas emission from all the volcanoes in all the world combined. Something that’s been building heat in our atmosphere at unprecedented rates. Something that’s been increasingly setting off the strange and deadly Hothouse Mass Casualty Events (HMCE). Events that appear ready to hit the innocent, the poor, and the vulnerable among us the hardest.

Over the past few decades, HMCEs, have occurred with increasing frequency during periods of extreme heat and drought that exceeded the scope and intensity of past heatwaves. These events resulted both in mass human mortality and in medical infrastructure crippling waves of heat injuries. These new, deadly heatwaves occurred in a world that was about 0.6 to 0.8 C hotter than 1880s averages. But as of the past two years, the global heat factor has cranked still higher — hitting 0.9 to 1.1 C above 1880s levels during 2014 and 2015 — and further increasing the likelihood of these dangerous events.
And according to a new scientific report from Dr. James Hansen — these events are about to become an ever-more permanent part of the global landscape. In essence, if fossil fuel burning continues, the poorest parts of the world who have contributed the least to the climate change problem will experience HMCEs with such a high frequency that many of these regions are going to become practically uninhabitable by the end of this Century. It’s a level of unfair and unequal treatment that’s difficult to stomach. For those who continue to burn fossil fuels, who continue to push fossil fuel burning through lobbying, market dominance, and short-sighted government policies, and who plan to burn these harmful fuels on into the future now appear to be involved in a kind of combined act of inflicted human habitat destruction and possible genocide.
On Wednesday, Dr. James Hansen, former head of GISS NASA, and one of the world’s foremost authorities on human-caused climate change, dropped another bombshell on an in-the-know scientific community that appears to be struggling to keep up with the velocity of what has now become aGlobal Warming Emergency. Hansen’s new report first takes a look at warming in retrospect — using historical temperature and extreme warming event data to show that the world has been radically altered by a rampant fossil fuel emission. Then, Hansen takes a look forward into what appears to be an increasingly hot and dangerous greenhouse gas warmed future.

(Through late 2015, Hansen’s data showed that human fossil fuel emissions continued along a path just above IPCC worst case ranges, and flirting with the lower edge of absolute worst case ranges. Hansen here identifies these carbon emissions as a global warming ‘Time Bomb.’ Image source: Dr. James Hansen.)

No More Cool Summers For Some Parts of the World

The paper found that the frequency of extreme heating events increased over the globe, even as the likelihood of cool or cold weather fell off. Though every region showed an increase in warm or hot events and a drop off in cool or cold events, some regions experienced more warming than others.
For example, in the US, summers cooler than the 1951 to 1980 average now occur only 19 percent of the time. Meanwhile, the frequency of extreme heating events 3 standard deviations outside the mid 20th Century average increased by an order of magnitude to 7 percent. These are strong shifts toward hotter summers for the US. But they are somewhat minor in comparison to shifts occurring in other parts of the world.
Hansen notes that in the Middle East and Mediterranean, rates of summer warming have increased to the point that there are now no summers that are cooler than average even as the period of summer seasonality has grown “considerably longer.” This statement is worth thinking about for a bit — essentially what’s happened is cool summers below the mid 20th Century average have been basically wiped out in the Med and Middle East. Cool summers there are a thing of a much less dangerous and far more pleasant past.

And looking at Hansen’s graph below we find that the impact of warming in many highly populated regions of the world is already far greater than within the United States:

(Shift to hotter Summers and Winters is now producing a greatly increased frequency of extremely hot summers even as it is steadily eliminating the likelihood of cool summers. Image source: Regional Climate Change and National Responsibilities.)

As the world continues to heat up, there is rising risk to human beings over broad regions. This is due to the fact that a warming world increases the latent heat of the atmosphere. When Ocean surfaces warm to above 35 degrees Celsius, this results in an increase in the amount of warm moisture in suspension in the atmosphere. For human beings, it makes it more difficult for heat to transfer way from the skin through evaporative cooling. At a 35 degree C Wet Bulb reading, the human body’s ability to cool itself breaks down — resulting in high risk of heat stroke and death if exposure continues for 1-2 hours.

The tropics and the Middle East in summer are in danger of becoming practically uninhabitable by the end of the century if business-as-usual fossil fuel emissions continue, because wet bulb temperature could approach the level at which the human body is unable to cool itself under even well-ventilated outdoor conditions.  Lesser warming still makes life more difficult and reduces productivity in these regions, because temperatures are approaching the limit of human tolerance and both agricultural and construction work are mainly outdoor activities.

Health-Risks, Violence, Climate Inequality and Responsibility

In addition to increasing the likelihood of hothouse mass casualty events, severe heatwaves, and increasing drought prevalence, Hansen notes added impacts to human beings and human societies. As we’ve seen with the Zika virus, disease vectors spread into higher Latitudes as the world warms — increasing the range of harmful and deadly tropical illnesses. Furthermore, studies indicate that violence increases dramatically in hotter regions. With each standard deviation increase in temperature patterns, group on group conflict has been observed to increase by 14 percent. This would already have increased conflict in the Med and Middle East by nearly 30 percent. For many regions of the world, if fossil fuel burning continues, warming is expected to shift a further 3-7 standard deviations off baseline. If the violence study findings are correct, this could double instances of group on group conflict for some parts of the world.

(Unequal climate change contributions, unequal impacts. Image source: Regional Climate Change and National Responsibilities.)

One final assertion of Hansen’s paper is that warming impacts and contributions are unequal. People living in Asia and Africa are seeing disproportionate warming even as they have contributed very little to the problem. And many of the regions now experiencing above average rates of warming could be rendered practically uninhabitable by Century’s end. People in the United States, Canada, Australia, Russia, Japan, and Northern Europe, though also suffering warming impacts, have been among those contributing the most to the problem and seeing the lowest rates of change in the form of extreme heat related events (though those experiencing ever more frequent droughts in the US Southwest may beg to differ). The Middle East’s own moderate national emissions contribution to global warming (though a rather high export contribution in the form of oil and gas sales) is matched by an extreme commitment to dangerous heatwaves for the region. This distribution represents a highly unequal and unfair spread of climate impacts and climate change responsibility. Yet one more reason why the industrial nations of the world should be getting their act together for a concerted and rapid transition away from fossil fuel use.
It’s worth noting that the Hansen paper does not assess the impact of other climate change related events such as extreme rainfall or sea level rise on regions that have contributed the most to the problem. It’s likely that vulnerable cities would see a widely distributed impact from the kind of multi-meter sea level rise Hansen warns is possible rippling across the globe. Portions of the US East and Gulf Coasts, in particular, have an extraordinary vulnerability to this climate change related threat.
Hat tip to TodaysGuestIs

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