<
https://www.sciencealert.com/termination-zero-our-predicament-may-be-totally-unprecedented>
"Since 2006, the amount of heat-trapping methane in Earth's atmosphere has been
rising fast and, unlike the rise in carbon dioxide (CO₂), methane's recent
increase seems to be driven by biological emissions, not the burning of fossil
fuels.
This might just be ordinary variability – a result of natural climate cycles
such as El Niño. Or it may signal that a great transition in Earth's climate
has begun.
Molecule for molecule, methane is a much more potent greenhouse gas than CO₂
but it lasts slightly less than a decade in the atmosphere compared with
centuries for CO₂. Methane emissions threaten humanity's ability to limit
warming to relatively safe levels.
Even more troubling, the rate at which methane is increasing in the atmosphere
has accelerated recently. Something like this has happened before: sudden
surges in methane marked the transitions from cold ice ages to warm
interglacial climates.
Methane was about 0.7 parts per million (ppm) of the air before humans began
burning fossil fuels. Now it is over 1.9 ppm and rising fast. Roughly
three-fifths of emissions come from fossil fuel use, farming, landfills, and
waste. The remainder is from natural sources, especially vegetation rotting in
tropical and northern wetlands.
Methane is both a driver and a messenger of climate change. We don't know why
it is now rising so rapidly, but the pattern of growth since late 2006
resembles how methane behaved during great flips in Earth's climate in the
distant past."
Via Rixty Dixet.
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
