Analysis of warming since 1881 shows most of the increase in global temperature happened before 1919 — before the more re-cent sharp rise in the amount of carbon dioxide in the atmosphere. said Thomas Karl, of the National Oceanic and Atmospheric Administration’s National Climatic Data Center in Asheville, N.C. While global climate warmed overall since 1881, it actually cooled from 1921 to 1979, Karl said
07 Dec 1989, Page 14 – Santa Cruz Sentinel at Newspapers.com
Briffa’s reconstruction shows exactly what Tom Karl said in 1989
Keith Briffa always struck me as an ‘honest broker’. I got the impression he didn’t care for the way Mikey Mann molested his tree ring data.
Tom Karl on the other hand always struck me as a ‘lying snake’.
I have a hard time understanding why they “benchmark” CO2 at about late 1800s, when it is clear that life has been on Earth for more than 500 million years, during most of which CO2 levels were close to a magnitude higher, and life thrived. I can see the argument that life has now adjusted to lower levels of CO2, and it might be damaging to it if CO2 were to rapidly increase. BUT if the space shuttle allows 5000 ppm, then the biological argument seems invalid. It is still a trace gas. Weather and climate factors in a high CO2 environment may be different, but one would have to again point to the success of the biosphere over 500 million years in a CO2 environment that averaged around 3500 ppm. And the downward trend of CO2 in atmosphere is more alarming in the long haul for the biosphere. So what do we as custodians of Earth want: ski seasons, or long term health for the biosphere? I think we should set the benchmark for CO2 higher, and recognize the geo-perspective on CO2, rather than only one century or so.
You are correct. The worst time to benchmark CO2 is during or near the end of an ice age. The cold oceans have sucked much of the CO2 from the atmosphere. During the last ice age, CO2 levels were at perhaps the lowest level in Earth’s history.