Posts
Words from the conservative Robertscribbler
Record-Hot 2016 Marks the Start of Bad Climate Consequences, Provides “Fierce Urgency” to Halt Worse Harms to Come
18
October, 2016
“…there
is now strong evidence linking specific [extreme] events or an
increase in their numbers to the human influence on climate.”
— Coumou
and Rahmstorf 2012.
“We
are confronted with the
fierce urgency of now.
…We may cry out desperately for time to pause in her passage, but
time is deaf to every plea and rushes on. Over the bleached
bones and jumbled residues of numerous civilizations are written the
pathetic words, ‘Too late.'” — Dr.
Martin Luther King, Jr. [emphasis
added]
****
2016
is on track to be a record-hot year for the history books.
Accumulations of heat-trapping gasses in the range of 402
ppm CO2 and 490 ppm CO2e have
pushed the global temperature trend into an inexorable upward rise.
Meanwhile, increasingly severe climate change-related events ranging
from mass coral bleaching, to glacial and sea ice melt, to tree
death, to ocean health decline, to the expanding ranges of tropical
infectious diseases, to worsening extreme weather events have
occurred the world over. This global temperature spike and related
ramp-up of extreme events continued throughout a year that is setting
up to follow 2014 and 2015 as the third record-hot year in a row.
Gavin Schmidt
With data now available through September, 2016 annual record (~1.25ºC above late 19th C) seems locked in.
(2015
saw a substantial jump in global temperatures. 2016 is also on track
to hit new record highs. The above graph, by Gavin Schmidt of NASA
GISS, provides a vivid illustration of an inexorable warming trend
with 2016 as the hottest year yet. According to Gavin, a strong new
record for 2016 appears to be a lock. Image source: Climate
of Gavin.)
Now, after
NASA’s report showing that September 2016 was 1.13 C hotter than
1880s averages (or 0.91 C hotter than NASA’s 20th-century baseline
measure),
this year is setting up to be the warmest ever recorded by a wide
margin. Overall, the first nine months of 2016 have averaged 1.25 C
above 1880s temperatures. Meanwhile, the climate year — which runs
from December through November — is tracking 1.26 C above 1880s
temperatures during the ten-month period of December to September.
2016
as much as 1.25 C Hotter than 1880s Averages
As
a result, it appears likely that 2016 will see temperatures in the
range of 1.19 C to 1.25 C hotter than 1880s averages. That’s about
0.1 C hotter than 2015 — which is pretty significant considering
the fact that the average rate of decadal warming
(the rounded rate of global warming every 10 years) has been in the
range of 0.15 C since the late 1970s. This year’s temperatures now
appear set to exceed 1998’s values by around 0.35 C — or about
one-third of the entire warming total seen since large-scale human
greenhouse gas emissions began during the late 19th century. This
excession should permanently put to rest previous
widely circulated false notions that global warming somehow stopped
following the strong El Nino year of 1998.
Many
responsible sources are
now warning that current temperatures are uncomfortably close to two
major climate thresholds — 1.5 C global warming and 2.0 C global
warming. At the current rate of warming, we appear set to exceed the
1.5 C mark in the annual measure in just one to two decades.
Hitting 2 C by or before mid-century has become a very real
possibility. Scientists
have been urging the global community to avoid 2 C warming before
2100 (and
1.5 C if at all possible), but the current path brings us to that
level of warming in just over 30-50 years, not over the 84 years
remaining in this century. And just maintaining current rates of
warming without significant added feedbacks from the Earth System
would result in Earth hitting close to 3 C warming by 2100 — a
level that would inflict severe harm to life on Earth, including
human civilizations.
(According
to NASA, September 2016 edged out September 2014 as the hottest
September in the 136-year climate record. This occurred while
the Equatorial Pacific was flipped into a cool phase, which
tends to lower global temperatures. Despite this natural
variability-related switch pulling global temperatures down, NASA
shows a globe in which few regions experienced below-average
temperatures and where the highest concentration of record-warm
temperatures are centered near the northern polar region. This
display of counter-trend warming and strong polar amplification are
both signature effects of human-caused climate change. Image
source: NASA
GISS.)
Focusing
back on 2016, it appears the La Nina that struggled throughout August
and early September is
again making a decent attempt to form, at
least as a weak event. This should tend to pull October, November and
December temperatures into the 1 to 1.1 C above 1880s departure
range. As a result, final averages for 2016 should be slightly lower
than averages for the period running from December to September. But,
as noted above, we are still on track to see a very significant jump
above the 2015 end atmospheric temperature totals.
Climate
Impacts from Added Global Heat Continue to Worsen
All
this extra heat in the system will work to worsen the already extreme
climate and weather events we are seeing. Potentials
for droughts, floods, heatwaves and wildfires will increase.
High atmospheric moisture loading will continue to pump up peak storm
potentials when storms do form. Added heat will tend to accumulate at
the poles more than in the tropics or middle latitudes. As a
result, upper-level
wind patterns will likely continue to see more anomalous features
along a worsening trend line.
Ice in all forms will see stronger heat forcings overall, adding risk
that both land and sea ice melt rates will increase.
(In
the mid-2010s, Earth entered a temperature range averaging 1 C above
pre-industrial levels. Such temperatures begin to threaten key
climate impacts like permafrost thaw, 3-4 meters of sea-level rise
from West Antarctic Ice Sheet melt, risk of up to 80 percent mountain
glacier loss, complete Arctic sea ice loss during summer, and 6-7
meters of sea level rise from Greenland melt. In the near 1 C range,
risks of these impacts, though a possibility, remain somewhat lower.
But as temperatures approach 1.5 and 2 C above pre-industrial levels,
risks rise even as West Antarctic glacial melt and polar ocean
acidification start to become serious factors. Image source: Solving
the Climate Stalemate.)
At
1 to 1.3 C above 1880s levels, we
should see a quickening in the rate of sea-level rise.
How much is uncertain. However, this temperature range is very close
to peak Eemian Stage levels when oceans were around
15 to 25 feet higher than they are today.
The current rapid rate of temperature change will also continue to
have worsening impacts on creatures who are adapted to inhabit
specific climate zones.
The
rapid rise in global temperatures is forcing an equally rapid
movement of climate zones toward the poles and up mountains.
This affects pretty much all life on Earth and unfortunately some
species will be hard-pressed to handle the insult as certain habitats
basically move off-planet. This
impact is particularly true for corals,
trees and other species that are unable to match the rapid pace of
climate zone motion. We have already seen very severe impacts in
the form of mass coral and tree death the world over. Warming in the
1 to 1.3 C range also provides an increasing ocean stratification
pressure — one that has already been observed to increase the
prevalence of ocean dead zones and one that will tend to shrink
overall ocean vitality and productivity.
Fierce
Urgency For Climate Action
Despite
all these negative impacts, we are still currently outside the
boundary of the worst potential results of climate change. Stresses
are on the rise from various related factors, but these stresses have
probably not yet reached a point of no return for human
civilization and
many of the reefs,
forests, and living creatures we have grown to cherish. Rapid
mitigation through a swift transition away from fossil fuels is still
possible. Such a response now has a high likelihood of successfully
protecting numerous civilizations while saving plant and animal
species across the planet. That said, at this point, some damage is,
sadly, unavoidable. But the simple fact that we are now starting to
face the harmful consequences of a century and a half of fossil fuel
burning is no excuse for inaction. To the contrary, the beginning of
these harms should serve as a clarion call for our redoubled efforts.
Links:
Hat
tip to Kevin Jones
Hat
tip to Florifulgurator
No comments:
Post a Comment
Note: only a member of this blog may post a comment.