Showing posts with label climate change. Show all posts
Showing posts with label climate change. Show all posts

Saturday 11 October 2014

Climate Change Accelerating

Methane levels as high as 2562 ppb were recorded on October 9, 2014, as illustrated by the image below.

Many grey areas show up in the image where QC (quality control) failed, as it was too hard to read methane levels in the respective area, apparently due to high moisture levels (i.e. snow, rain or water vapor) in the atmosphere.


As above image illustrates, cloud cover is high over the Arctic, while there is also precipatation in the form of snowfall.

In other words, high levels of methane (above 1950 ppb, colored yellow) could be present over a much larger part of the Arctic Ocean, while methane in these grey areas could be even higher than the measured peak level of 2456 ppb.

This appears to be confirmed by persistent high methane levels over vast areas across the Arctic Ocean both in the morning (top part of the image further above) and in the afternoon (bottom part of image) on 9 October 2014.

Methane levels are this high over the Arctic Ocean for the number of reasons, including:
  • The Gulf Stream keeps pushing warm water into the Arctic Ocean.
  • The resulting eruptions of methane from the seafloor of the Arctic Ocean constitute a feedback that accelerates warming in the Arctic. 
  • As the Arctic warms up more rapidly than the rest of Earth, the Arctic's ice and snow cover will decline, further accelerating warming in the Arctic.
  • As the Arctic warms up more rapidly than the rest of Earth, the speed at which jet streams circumnavigates the Northern Hemisphere will weaken, making it meander more, resulting in a greater frequency and intensity of extreme weather events, such as heat waves, droughts and wildfires. 
Here's an example of intense warming. Look at what is currently happening on Greenland.

As the image above right shows, sea surface temperature anomalies as high as +1.89°C hit the North Atlantic (on October 8, 2014). 

Furthermore, high cloud cover over the Arctic (image further above) makes it hard for the heat there to radiate out into space, further contributing to high temperature anomalies.

The image on the right shows high temperature anomalies over Greenland and parts of the Arctic Ocean on October 11, 2014. Note that anomalies are averaged out over the course of the day (and night).

The image below (right) shows anomalies at the top end of the scale hitting large parts of Greenland at a specific time during this day. The left part of the image below shows how this could happen, i.e. jet streams curling around Greenland trapping warm air inflow from the North Atlantic.


As said, as the Arctic warms up more rapidly than the rest of Earth, the speed at which jet streams circumnavigate the Northern Hemisphere will weaken, making the jets meander more and creating patterns that can trap heat (or cold) for a number of days over a given area. Due to the height of its mountains, Greenland is particularly prone to be increasingly hit by heatwaves resulting from such blocking patterns. Warming changes the texture of snow and ice, making it more slushy and darker, which also makes that it absorbs more of the sunlight's heat, further accelerating melting.

As Paul Beckwith warns in an earlier post, melt rates on Greenland have doubled in the last 4 to 5 years, and melt rates on the Antarctica Peninsula have increased even faster. Based on the last several decades, melt rates have had a doubling period of around 7 years or so. If this trend continues, we can expect a sea level rise approaching 7 meters by 2070.

From: More than 2.5 m sea level rise by 2040
These are all indications that the pace of climate change is accelerating in many ways, the most dangerous one being ever larger methane eruptions from the Arctic Ocean's seafloor. As the image below shows, sea surface temperature anomalies are very high in the Arctic Ocean, indicating very high temperatures under the surface.



U.S. Secretary of State John Kerry recently said: “There are now – right now – serious food shortages taking place in places like Central America because regions are battling the worst droughts in decades, not 100-year events in terms of floods, in terms of fires, in terms of droughts – 500-year events, something unheard of in our measurement of weather.” Warning about looming catastrophe, Kerry adds: “Life as you know it on Earth ends. Seven degrees increase Fahrenheit (3.9°C), and we can't sustain crops, water, life under those circumstances.”

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.




Saturday 31 May 2014

How many deaths could result from failure to act on climate change?

A recent OECD study concludes that outdoor air pollution is killing more than 3.5 million people a year globally. The OECD estimates that people in its 34 Member countries would be willing to pay USD 1.7 trillion to avoid deaths caused by air pollution. Road transport is likely responsible for about half.

A 2012 report by DARA calculated that 5 million people were dying each year from climate change and carbon economies, mostly from indoor smoke and (outdoor) air pollution.

Back in 2012, a Reuters report calculated that this could add up to a total number of 100 million deaths over the coming two decades. This suggests, however, that failure to act on climate change will not cause even more deaths due to other causes.

Indeed, failure to act on climate change could result in many more deaths due to other causes, in particular food shortages. As temperatures rise, ever more extreme weather events can be expected, such as flooding, heatwaves, wildfires, droughts, and subsequent crop loss, famine, disease, heat-stroke, etc.

So, while currently most deaths are caused by indoor smoke and outdoor air pollution, in case of a failure to act on climate change the number of deaths can be expected to rise most rapidly among people hit by famine, fresh water shortages, as well as wars over food, water, etc.

How high could figures rise? Below is an update of an image from the earlier post Arctic Methane Impact with a scale in both Celsius and Fahrenheit added on the right, illustrating the danger that temperature will rise to intolerable levels if little or no action is taken on climate change. The inset shows projected global number of annual climate-related deaths for these two scenarios, i.e. no action and little action, and also shows a third scenario of comprehensive and effective action that would instead bring temperature rise under control.

[ click on image to enlarge ]
For further details on a comprehensive and effective climate plan, see the ClimatePlan blog.





Wednesday 16 April 2014

Near-Term Human Extinction

Global Warming and Feedbacks

Is there a mechanism that could make humanity go extinct in the not-too-distant future, i.e. within a handful of decades?

Most people will be aware that emissions due to human activity are causing global warming, as illustrated by the arrow marked 1 in the image on the left. Global warming can cause changes to the land, to vegetation and to the weather. This can result in wildfires that can in turn cause emissions, thus closing the loop and forming a self-reinforcing cycle that progressively makes things worse.

Furthermore, less forests and soil carbon also constitute a decrease in carbon sinks, resulting in carbon that would otherwise have been absorbed by such sinks to instead remain in the atmosphere, thus causing more global warming, as illustrated by the additional downward arrow in the image on the right. In conclusion, there are a number of processes at work that can all reinforce the impact of global warming.

Emissions can also contribute more directly to land degradation, to changes in vegetation and to more extreme weather, as indicated by the additional arrow pointing upward in the image on the right. A recent study by Yuan Wang et al. found that aerosols formed by human activities from fast-growing Asian economies can cause more extreme weather, making storms along the Pacific storm track deeper, stronger, and more intense, while increasing precipitation and poleward heat transport.

Accelerated Warming in the Arctic

Similar developments appear to be taking place over the North Atlantic. Huge pollution clouds from North America are moving over the North Atlantic as the Earth spins. In addition, the Gulf Stream carries ever warmer water into the Arctic Ocean. As the image below shows, sea surface temperature anomalies at the highest end of the scale (8 degrees Celsius) are visible off the coast of North America, streching out all the way into the Arctic Ocean.


As said, feedbacks as are making the situation progressively worse. Feedback loops are causing warming in the Arctic to accelerate. Warming in the Arctic is accelerating with the demise of the snow and ice cover in the Arctic, and this is only feedback #1 out out many feedbacks that are hitting the Arctic, as described in an earlier post. As the temperature difference between the equator and the Arctic decreases, the Jet Stream is changing, making it easier for cold air to move out of the Arctic and for warm air from lower latitudes to move in (feedback #10).


Abrupt Climate Change leading to Extinction at Massive Scale

The danger is that, as temperatures over the Arctic Ocean warm up further and as the Gulf Stream carries ever warmer water into the Arctic Ocean, large quantitities of methane will erupt abruptly from the seafloor of the Arctic Ocean, adding a third kind of warming, runaway warming resulting in abrupt climate change, and leading to mass death, destruction and extiction of species including humans.

Persistence of such a progression makes it inevitable that the rest of Earth will follow the huge temperature rises in the Arctic. Massive wildfires will first ignite across higher latitudes, adding further greenhouse gas emissions and causing large deposits of soot on the remaining snow and ice on Earth, with a huge veil of methane eventually spreading around the globe. The poster below, from an earlier post, illustrates the danger.

[ click on image to enlarge - note that this is a 1.8 MB file that may take some time to fully load ]
Views by Contributors

How likely is it that the above mechanism will cause human extinction within the next few decades? What views do the various contributors to the Arctic-news blog have on this?

Guy McPherson has long argued that, given the strengths of the combined feedbacks and given the lack of political will to take action, near-term human extinction is virtually inevitable.

In the video below, Paul Beckwith responds to the question: Can climate change cause human extinction?


Further contributors are invited to have their views added to this post as well. While many contributors may largely share Paul Beckwith's comments, it's important to highlight that contributors each have their own views, and this extends to their preference for a specific plan of action.

Geo-engineering

One of the more controversial issues is the use of geo-engineering. Guy McPherson doesn't believe geo-engineering will be successful. In the video below, Paul Beckwith gives his (more positive) views on this.


I must admit that the lack of political will to act is rather depressing, especially given the huge challenges ahead. So, I can understand that this can make some of us pessimistic at times. Nonetheless, I am an optimist at heart and I am convinced that we can get it right by giving more support to a Climate Plan that is both comprehensive and effective, as discussed at ClimatePlan.blogspot.com