2014, according to Japanese, NOAA, and NASA measurements,
was approximately 0.2 degrees Fahrenheit warmer than any previous measured
year, or about 2 degrees Fahrenheit warmer globally than the early 1900s. 6 of its 12 months set monthly heat
records. Scientists are now confident
about asserting that this is the warmest it has been in the past 50,000 years,
and we are rapidly closing in on clearly being warmer than at any time in the
last 5 million years.
As James Hansen has recently noted, the global temperature
more or less parallels the increase or decrease in carbon in the atmosphere,
with each doubling being associated with a 4 degrees Centigrade (about 7
degrees Fahrenheit) increase in global temperature. About 2/3-3/4 of this is from the effects of
atmospheric carbon dioxide itself, and 1/3-1/4 due to linked increases in black
carbon, methane (CH4), and the like.
Thus, since we are about halfway between our 1800s starting point of
250-280ppm of atmospheric carbon and a doubling of that amount, we have
essentially “baked in” an increase of about 2.3 degrees Centigrade or 4 degrees
Fahrenheit – the level at which, according to some scientists, catastrophic
effects start to occur. What consequences? Movement of drought-ridden subtropical zones
north to encompass much of the US except the Northeast, much of Southern Europe
through France and Germany, and places such as the Fertile Crescent, India and
Southern China. Loss of all Arctic sea
ice as well as some Greenland and Antarctic ice, for a potential total
(including expansion of the ocean through warming) of perhaps 25-80 feet. Loss of at least 1/3 of presently arable
land, to be replaced by Canadian, Argentinian, and Siberian land that is
presently mostly tundra and permafrost, and which would likely become
fly-ridden, easy-to-burn-via-methane, peat swamps. Speed of winds in storms on average might
increase by 10 mph.
But the “worst consequences” occurring if we go ahead and
use more than 17% of present coal reserves, more than 50% of available oil and
natural gas, and more than a small fraction of tar sands and oil shale, are far
more dire. A rise in sea level of
216-240 feet. Possibly, iron blooms periodically
releasing unbreathable sulfuric acid, making living near the new sea coasts
impossible. Loss of perhaps 90% of
arable land, making it impossible to feed more than about 1 billion people on
minimal rations. Acidification of oceans
that means destruction of all ocean-based food sources. Heat that makes working outside during 6
months of the year a death sentence.
Storms in which the wind speed increases by more like 40 mph, so that
the average high wind is a 110-mph hurricane, and somewhere in the world just
about every year there is a 200-mph hurricane bearing down on humanity.
So how are we doing in avoiding “worst consequences”? Well, there are lots of encouraging
superficial signs, including international agreements, preliminary data
suggesting that Europe and the USA are decreasing their carbon emissions in
constant terms, and so on. The problem
is that such data is partial – for example, the emissions data just tracks
carbon emissions via industry-based estimates and for those sources we don’t
know about. There’s really only one
holistic indicator, approximate as it is:
the amount of CO2 in the atmosphere measured at the Mauna Loa volcano in
Hawaii. You can find the data by
googling “CO2 Mauna Loa”.
This set of measurements was started by Charles Keeling in
1950, and he picked a spot high on Mauna
Loa because it was out of the way of the kind of things that would contaminate
measurements. Interestingly, it has been
joined in the last few years by a new measure based on widely dispersed global
sites, which until recently had tracked 10 ppm less than Mauna Loa. In the latest data, it is now virtually
identical at at 400 ppm, suggesting that the original global sites were
contaminated more than expected and biased in a downward direction. At any rate, the new global measurements,
like the old, tend to “smooth out” the more jagged spikes and dips in CO2 ppm
yearly growth as measured by Mauna Loa.
So Mauna Loa is more volatile, but the two agree in both the amount and
trend over periods of perhaps 5 years or so.
What is Mauna Loa saying about the last 3 years? These years, in which the world economy is
mostly flat or down – which should lead to decreased carbon emissions – and various
policies have been implemented to reduced emissions, notably in Europe, are
also the first years in which the CO2 growth has been above 2 for each
year. In fact, according to the global “smoothed”
data, it has been above 2.4 ppm each year.
Not only are we not making progress; things are getting worse.
How can this be?
Speculation is a bit early, but what it suggests is that US efforts are
counteracted by attempts to “grow domestic oil production”, and that European
efforts are more than counteracted by Chinese increased coal use (despite its
rhetoric). I conclude that we must run
faster to fall behind slower, and at an amazing speed just to stay in the same
place. Happy New Year.
