“Perhaps the most worrisome threat is that because the Arctic is warming so much faster than the globe as a whole, the permafrost — soil that remains frozen year-round — is thawing. As it does, organic matter which is trapped within can decay, and when it does it releases CO2 into the atmosphere, except those places where instead of releasing CO2 it releases CH4.” — Tamino.
With the Northern Hemisphere Pole warming at a rate 2-3 times faster than the rest of the globe, there’s a risk that we start to set off a kind of runaway warming feedback. We may be near that threshold now… God help us if we’ve crossed it…
Prior to 2015, the highest annual rate of atmospheric CO2 increase occurred in 1998 at 2.9 ppm. This record was broken in 2015 when atmospheric CO2 levels climbed by 3.05 ppm. But so far this year, the rate of increase for this heat-trapping gas is a stunning 3.68 parts per million above comparable monthly averages seen during 2015. That’s nearly four times the rate of atmospheric accumulation since the early 1960s. A level of increase that almost guarantees that 2016 will shatter 2015’s record for CO2 gain and set a new ominous benchmark for a ramping accumulation of hothouse gasses.
(Big jumps in month to month, 2015 to 2016 CO2 concentrations make it almost certain that the annual rate of increase in this greenhouse gas’s concentration will be a new global record. Image source: NOAA ESRL.)
Human Fossil Fuel Burning, A Carbon Saturated Ocean, and Amplifying Feedbacks
The baseline driver for this amazing rate of increase is a global carbon emission in the range of 13 billion tons every year (a rate that is about 30 percent faster than during 1998). Efforts on the part of China and the rest of the world to curtail coal emissions did result in a leveling off of these human emissions during 2014 and 2015. But this action only managed to achieved a plateau in the rate at which heat-trapping gasses hit the atmosphere at or near new record high levels. A rate of emissions that is about ten times faster than the out-gassing of heat trapping airs which set off the Paleocene – Eocene Extinction about 55 million years ago.
Wagging that baseline was a strong El Nino. During El Nino years, the Tropics heat up. This results in less CO2 being absorbed by the global Equatorial Ocean even as droughts and wildfires related to the Nino climate variation pump more carbon out of the world’s soils and vegetation.
But also impacting rate of CO2 rise is what is now an ongoing set of Earth System Feedbacks related to human-caused climate change. The added 1.2 C worth of warming since 1880 that 2016 is likely to experience helps to amplify the El Nino drought and ocean warming signal resulting in even less carbon uptake and producing even more carbon feedback. In addition, oceans saturated with carbon due to atmospheric CO2 levels hitting near 408 ppm are already able to hold less of the stuff in suspension. So it takes less relative heat force to further shut down that uptake. In addition, the warming Arctic is starting to unearth a number of previously frozen carbon stores. And record high global temperatures are now generating a weak but troubling signal that some of these stores may be starting to release.
Deposits of frozen methane, a potent greenhouse gas, and carbon dioxide lie beneath permafrost in Arctic regions. About a quarter of the Northern hemisphere is covered by permafrost. As the environment warms and the permafrost thaws, these deposits can be released into the atmosphere and present a risk of runaway warming.
(Smoothed annual rate of atmospheric CO2 increase provided by Tamino shows that the pace of CO2 accumulation has increased by about 0.25 ppm per decade since the 1960s. The primary driver of this increase is human fossil fuel burning. But an increasingly substantial driver is the saturation of global carbon stores coupled with emerging amplifying feedbacks. Failure to reduce and halt fossil fuel burning as soon as possible will result in a worsening and intensifying of these warming feedbacks — putting at risk a catastrophic runaway warming scenario that we should strive to avoid at all costs. Image source: Tamino.)
In this context, the big 2016 jump in atmospheric CO2 levels looks pretty grim. And we’ve seen no respite in June when the first three weeks were about 4.4 ppm CO2 higher than during the same period in 2015. In fact, it appears that the rate of CO2 drop off for this year is lagging a bit behind trend line. A reduced pace of loss that looks pretty bad coming off of such amazing highs for the first five months of the year and during a time when the carbon-loaded Arctic has been so ridiculously warm.
NASA (please support public, non special interest based science like the fantastic and often life-saving work done at NASA and NOAA)
Hat tip to Wili
Hat tip to John McCormack