Posted on 03/19/2014 6:15:30 AM PDT by Mrs. Don-o
400 PPM: What’s Next for a Warming Planet Concentrations of greenhouse gases in the atmosphere have reached this level for the first time in millions of years. What does this portend? »
On May 2, after nightfall shut down photosynthesis for the day in Hawaii, carbon dioxide levels in the atmosphere touched 400 parts-per-million there for the first time in at least 800,000 years. Near the summit of volcanic Mauna Loa—where a member of the Keeling family has kept watch since 1958—sensors measured this record through sunrise the following day. Levels have continued to dance near that benchmark in recent days, registering above 400 ppm for the first time in eons after midnight on May 7. When the measurements started the daily average could be as low as 315 ppm, already up from a pre-industrial average of around 280 ppm.
This measurement is just the hourly average of CO2 levels high in the Hawaiian sky, but this family’s figures carry more weight than those made at other stations in the world as they have faithfully kept the longest record of atmospheric CO2. Arctic weather stations also hit the hourly 400 ppm mark last spring and this one. Regardless, the hourly levels at Mauna Loa will soon drop as spring kicks in across the northern hemisphere, trees budding forth an army of leaves hungrily sucking CO2 out of the sky. 5-2-5-7-2013-mauna-loa
Courtesy of Scripps Institution of Oceanography
It may be next year before the monthly average level reaches 400 ppm—and yet longer still until the annual average reaches that number.
But there is no question that the world continues to inexorably climb toward higher levels of greenhouse gas concentrations. Barring economic recessions, the world may be lucky to stop at 450, 500 or even beyond. Last year, humanity spewed some 36 billion metric tons of greenhouse gases, up from 35 billion the year before.
In the coming year, Scientific American will run an occasional series, “400 ppm,” to examine what this invisible line in the sky means for the global climate, the planet and all the living things on it, including human civilization. Some scientists argue we passed the safe level for greenhouse gas concentrations long ago, pointing to the accelerating impacts, from extreme weather to the meltdown of Arctic sea ice. Others argue that we have yet more room to burn fossil fuels, clear forests and the like—but not much—before catastrophic climate change becomes inescapable. And the international community of nations has agreed that 450 ppm—linked to a rise of 2 degrees Celsius in global average temperatures—should not be exceeded. We are not on track to avoid that limit, whether you prefer the economic analysis of experts like the International Energy Agency or the steady monitoring of mechanical sensors.
The last time CO2 levels at Mauna Loa were this high, Homo sapiens did not live there. In fact, the last time CO2 levels are thought to have been this high was more than 2.5 million years ago, an era known as the Pliocene, when the Canadian Arctic boasted forests instead of icy wastes. The land bridge connecting North America and South America had recently formed. The globe’s temperature averaged about 3 degrees C warmer, and sea level lapped coasts 5 meters or more higher. co2-levels-over-800000-years
Courtesy of Scripps Institution of Oceanography
The world will change again due to human activity and associated emissions of CO2, perhaps causing another set of coral reef extinctions like those found during the Pliocene, among other impacts. When Charles D. Keeling first started his measurements, CO2 made up some 317 ppm of the air we breathe and climate change was already a concern thanks to the work of John Tyndall, Svante Arrhenius and Guy Callendar. Every year since 1958 the sawtoothed line depicting Keeling’s measurements—readings kept up by his son Ralph—has climbed up, capturing the rise in greenhouse gas concentrations as well as the world’s breath. keeling-curve
Courtesy of Scripps Institution of Oceanography
What can be done? In the short term, more potent but shorter-lasting greenhouse gas emissions could be curbed or a concerted effort to develop CO2 capture and storage technology could be undertaken. Whether we do that or not, given CO2′s long lifetime in the atmosphere, the world will continue to warm to some extent; at least as much as the 0.8 degree C of warming to date is likely thanks to the CO2 already in the atmosphere.
At present pace, the world could reach 450 ppm in a few short decades. The record notches up another 2 ppm per year at present pace. Human civilization developed and flourished in a geologic era that never saw CO2 concentrations above 300 ppm. We are in novel territory again and we show no signs of slowing to get our bearings, let alone stopping.
Thanks that’s very helpful. I will have to remember the water vapor contribution from now on.
I wonder if they have ever set CO`2 readers on the roofs of liberal houses.
How sad that Scientific American has gone from a journal of solid science to a dumbed-down rag for ecohysterics.
Better the temps go up than down!
They did a similar thing here in Pittsburgh back in the 70’s.
They strategically located all of the air pollution monitors over bus stops where old diesel buses would sit and idle for extended periods of time.
Pre-HISTORIC levels???
Pre =(before)
Historic(history)
How do they even know what THOSE levels WERE???
I cannot believe how STUPID these folks are, nor how STUPID they think WE are.
They use proxy measures: tree rings, ice cores, sediment cores. They are actually pretty good proxies if you know what you’re looking for.
The current rise in CO2 levels did not begin until all the mexicans came up here and brought their frijoles and burritos, which increased the flatulence levels in North America.
I just wish the powers that be would stop spraying crap in the atmosphere here.. took the dogs out this morning, the first thing I see is chemtrails as distinct as can be over the South Bay.. they did railroad tracks this morning, I’m sure they’ll be playing tic tac toe soon enough..
I hear rich folks and corporate types and scientists are behind efforts to modify the atmosphere to inhibit global warming.. they call it geoengineering.
.. and apparently politicos and local officials and celebs and the media are either clueless or unwilling to challenge much mess even mention it themselves.
I know one thing, Man-made gullibility is a cheap commodity these days.. and some are willing to go all in with no thought for future ramifications of policies the Nazis would readily embrace.
Junk science? Heck, junk planet.. sadly, they forget, no one gets out alive.. and they feel to see how they are speeding the planet purging process, not slowing anything.
The sky is falling, the sky is falling! /sarc
The definition of greenhouse gase is that they hold the
heat that the sun puts down on the earth, onto the earth.
The whole atmosphere we live is a mixture of greenhouse
gases, and we couldn’t live on this planet temperature
wise without the atmosphere as it would go down to minus
150 at night as all the heat from the day
would all escape.
And of the mixture of gases in the air around us, CO2
actually transfers heat faster, than most gases in the
air mixture; IE it has less insulation value
than O2 and N2 that make up 98% of the air.
Guys making thermopane windows tried CO2 and found it
transfers heat faster than air... So if CO2 is one part
in 2500, in 2000, in 3000, ETC, in the whole air mixture,
which is all the greenhouse gase mixture we live in,
it doesn’t matter. And we could not, temperature wise
live here,, if we didn’t have the air mixture, including
CO2 needed for plants to raise our food.
ONE PART CO2 IN 2500 DOES NOT MEANS SQUAT...
Of course you get problems like the AGW HOAX getting
traction and support... because folks are not
taught real science nowadays..Ed
Money. Lots and lots of money.
Regardless, the hourly levels at Mauna Loa will soon drop as spring kicks in
The point of that graph being that temperature change leads the CO2 change.
q10
http://www.bozemanscience.com/q10-the-temperature-coefficient
respiration is a chemical reaction.
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