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.
What say ye?
Wonder how much a prehistoric SUV would sell for if I could dig one up.
Would that be Ice Age prehistoric levels?
Sure, get a sample from the top of a volcano.
I vote yes, this should give the “population control” crowd the vapors.
Lot of heavy breathing going on back in the day? (800,000 years ago) Or, was it the CO2 being emitted from those scary SUV’s?
Well I say that they should have tossed the reading for the simple reason that the volcano is active.
A. Volcanoes
~~~~~~~~~~~~
Q. What is Mauna Loa?
A. A Volcano...
So, having a sensor at the top of an active volcano is a good idea..............................
Better that than another glacier build up here in Wisconsin! :)
A nice diversion and worthy of consideration. However, my first proposal is the urge the ‘Keeling’ family to take their highly accurate and scientific CO2 readings somewhere other than on the precipice of an active volcano.
This article mixes the (fraud) concepts of AGC and AGW. This seems to be a trend. Global “change” is a more flexible con, but doesn’t sell to the public like global “warming”.
This is just the NOAA way of doing things....place your dispersed geographical temperature sensors near the exhausts of building heating systems etc.....
To believe these amateurs’ loggings requires suspension of all disbelief in reality.
My rough interpretation of the data shown in the figures-
1. Daily CO2 conc from the 2nd to the 7th is fairly constant, on the 8th where it hits 400, the data is clearly an an artifact perhaps caused by an instrument malfunction or burp from the volcano. Check your instruments.
2. The long term data is clearly cyclical and the data from 1958 is a short term sample whereas the core data is averaged over hundreds or even thousands of years. You cannot compare the two.
3. The observatory data shows a constant rate of increase over 50 years. Since the amount of CO2 generated over those 50 years has not been increasing dramatically during that time, the rate of increase should be greater now than in the past. It is not.
Imagine a stadium with 100,000 seats. Now imagine 40 seats are left empty while the rest have someone in them to give you an idea of how little 400 ppm is.
Correction to my previous post. The 2nd comment should read “HAS been increasing dramatically”.
Apologies
Nobody ever asks the climate alarmists, "OK, so what is the IDEAL CO2 level and earth surface temperature?" As a gardener, my preferences are clear: more and more.
I'm glad my compost pile generates robust amounts of heat and CO2. If everybody had a compost pile, maybe I'd reach my target climate: the pretty, pleasant, practical Pliocene.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.