Showing posts with label 2015. Show all posts
Showing posts with label 2015. Show all posts

Sunday 26 April 2015

Methane levels as high as 2845ppb

Methane levels as high as 2845 parts per billion (ppb) were recorded on April 25, 2015, as illustrated by the image below.


This is an extremely high peak. The average daily peak in 2015 until May 1 was 2371 ppb, while the highest daily mean ranged from 1807 ppb (January 10) to 1829 ppb (April 22). Daily peaks and daily highest mean levels in 2015 are shown on the image below.



These peaks are much higher than they were in previous years, as illustrated by the image below, from an earlier post and showing the average highest peak readings in 2013 and 2014 at selected altitudes..


Peak readings in above image are averages over April 2013 and April 2014. On specific days, peak readings could be much higher, e.g. on April 28, 2014, methane levels were recorded as high as 2551 ppb at 469 mb. As said, methane levels as high as 2845 ppb were recorded on April 25, 2015, while the average peak for the first four months of 2015 was 2371 ppb, and this average was calculated from peaks across altitudes.

The table below shows the altitude equivalents in mb (millibar) and feet.
56,925 ft44,689 ft36,850 ft30,569 ft25,543 ft19,819 ft14,383 ft8,367 ft1,916 ft
74 mb147 mb218 mb293 mb367 mb469 mb586 mb742 mb945 mb

Peak levels in April appear to be rising strongly each year, following higher peak readings during previous months, especially at higher altitudes, i.e. especially the Arctic Ocean. It appears that much of the additional methane originating from the higher latitudes of the Northern Hemisphere has moved closer to the equator over the past few months, and is now accumulating at higher altitudes over the continents on the Northern Hemisphere, i.e. Asia, Europe, North America and north Africa.

Further analysis of the rise in global mean methane levels appears to confirm the above. The image below shows methane levels on April 22, over three years. While there appears to be little or no rise in mean methane levels at low altitudes, the rise is quite profound at higher altitudes.  

[ click on image to enlarge ]
Things look set to get worse. As shown by the image below, from an earlier post, global methane levels have risen sharply from a low of 723 ppb in 1755. Mean methane levels were as high as 1839 ppb in 2014. That's a rise of more than 254%.
As that post concluded a year ago, it appears that the rise of methane in the atmosphere is accelerating. What can we expect? As temperatures can be expected to continue to rise and as feedbacks start to kick in, this may well constitute a non-linear trend. The image below shows a polynomial trend that is contained in IPCC AR5 data from 1955 to 2011, pointing at methane reaching mean global levels higher than 3000 ppb by the year 2030. If methane starts to erupt in large quantities from clathrates underneath the seafloor of the Arctic Ocean, this may well be where we are heading. 




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



The 2845 ppb recorded on April 25, 2015, is an extremely high peak. The average daily peak in 2015 until now was 2372...
Posted by Sam Carana on Monday, April 27, 2015

Thursday 23 April 2015

It's time to 'Do the math' again

By David Spratt

Have we gone mad? A new report released today explains why contemporary climate change policy-making should be characterised as increasingly delusional.

As the deadline approaches for submissions to the Australian government's climate targets process, there is a flurry of submissions and reports from advocacy groups and the Climate Change Authority.

Most of these reports are based on the twin propositions that two degrees Celsius (2°C) of global warming is an appropriate policy target, and that there is a significant carbon budget and an amount of "burnable carbon" for this target, and hence a scientifically-based escalating ladder of emission-reduction targets stretching to mid-century and beyond.

A survey of the relevant scientific literature by David Spratt, "Recount: It's time to 'Do the math' again", published today by Breakthrough concludes that the evidence does not support either of these propositions.

The catastrophic and irreversible consequences of 2°C of warming demand a strong risk-management approach, with a low rate of failure. We should not take risks with the climate that we would not take with civil infrastructure.

There is no carbon budget available if 2°C is considered a cap or upper boundary as per the Copenhagen Accord, rather than a hit-or-miss target which can be significantly exceeded; or if a low risk of exceeding 2°C is required; or if positive feedbacks such as permafrost and other carbon store losses are taken into account.

Effective policy making can only be based on recognising that climate change is already dangerous, and we have no carbon budget left to divide up. Big tipping-point events irreversible on human time scales such as in West Antarctica and large-scale positive feedbacks are already occurring at less than 1°C of warming. It is clear that 2°C of climate warming is not a safe cap.

In reality, 2°C is the boundary between dangerous and very dangerous climate change and 1°C warmer than human civilisation has ever experienced.

In the lead up to the forthcoming Paris talks, policy makers through their willful neglect of the evidence are in effect normalising a 2.5–3°C global warming target.

This evidence in "Recount: It's time to 'Do the math' again" demonstrates that action is necessary at a faster pace than most policy makers conceive is possible.



Related

- It's time to 'Do the math' again
http://www.climatecodered.org/2015/04/its-time-to-do-math-again.html

- RECOUNT - It's time to 'Do the math' again
http://media.wix.com/ugd/148cb0_938b5512abfa4d4e965ec8cc292893f7.pdf

- Two degrees of warming closer than you may think
http://arctic-news.blogspot.com/2015/02/two-degrees-of-warming-closer-than-you-may-think.html

- The real budgetary emergency and the myth of "burnable carbon"
http://arctic-news.blogspot.com/2014/05/the-real-budgetary-emergency-and-the-myth-of-burnable-carbon.html

It's time to 'Do the math' again | by David Spratt http://arctic-news.blogspot.com/2015/04/its-time-to-do-math-again.html

Posted by Sam Carana on Thursday, April 23, 2015