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Global Warming 'Undeniable,' Report Says
BergZ writes "Scientists from around the world are providing even more evidence of global warming. 'A comprehensive review of key climate indicators confirms the world is warming and the past decade was the warmest on record,' the annual State of the Climate report declares. Compiled by more than 300 scientists from 48 countries, including Canada, the report from the National Oceanic and Atmospheric Administration said its analysis of 10 indicators that are 'clearly and directly related to surface temperatures, all tell the same story: Global warming is undeniable.'"
This particular report doesn't specify causes. It just goes over the temperature data and factors directly related to it (like humidity and glaciation). Even if the deniers could pick out one of these datasets and show that's its problematic, there would still be 9 others going the other direction--a textbook case of the Strawman.
Anthropogenic factors are proven out in other studies. There isn't a legitimate debate about that anymore, either.
The debate that's left is in the exact effects and what we can do about it. Low levels of extra CO2 in the atmosphere may actually be beneficial, but we've almost certainly blown way beyond that. Then there are large scale geoengineering projects (like putting a solar shield at L1), which are both expensive and may have unknown consequences. They're being discussed because there aren't a lot of better ideas.
Not a typewriter
The data as presented indicates a recent warming trend, but does not say anything about whether this is man-made or not; a 0.5deg rise in 50 years is extremely small in the scheme of things, and drawing the usual alarmist conclusions from this is quite unfounded.
So read the report itself:
The NOAA Annual Greenhouse Gas Index (AGGI) shows radiative forcing relative to 1750, of all the long-lived greenhouse gases indexed to 1 for the year 1990. Since 1990, radiative forcing from greenhouse gases has increased 27.5%.
Nitrous oxide (N2O) and sulfur hexafluoride (SF6) are important atmospheric trace gases with significant man-made sources. Nitrous oxide has the third strongest anthropogenic climate forcing after CO2 and CH4 and is considered a major greenhouse gas (Butler 2009).
The atmospheric N2O budget is out of balance by one-third as a result of man-made emissions, primarily through emissions from nitrogen fertilizers (Crutzen et al. 2007).
Atmospheric greenhouse gas concentrations continued to rise, with CO2 increasing at a rate above the 1978 to 2008 average. The global ocean CO2 uptake flux for 2008, the most recent year for which analyzed data are available, is estimated to have been 1.23 Pg C yr-1, which is 0.25 Pg C yr-1 smaller than the long-term average and the lowest estimated ocean uptake in the last 27 years. At the same time, the total global ocean inventory of anthropogenic carbon stored in the ocean interior as of 2008 suggests an uptake and storage of anthropogenic CO2 at rates of 2.0 and 2.3 ±0.6 Pg C yr-1 for the decades of the 1990s and 2000s, respectively.
In the tropics this increase has been formally attributed to anthropogenic change over the 1988–2006 period (Santer et al. 2007).
all the time series show an underlying rise in OHC consistent with our understanding of anthropogenic climate change.
I mean, the evidence is all over the report. The only thing stopping them from saying that it is conclusively man made is that 1) it's probably impossible to prove it and 2) there might always be some evidence of non anthropogenic warming contributing to the cause but not accounting for all of it.
My work here is dung.
You do realize that the rate of warming at the end of the last glaciation is about two orders of magnitude than the rate of warming we're experiencing today, right?
Yes, the current rate has been experienced before -- the Paleocene-Eocene Thermal Maximum was the last analogous period. But that was 56mya. And anyway, I don't think we want to repeat it. It changed the world so much that we give the subsequent era a new name (the Eocene).
I hate to bring up our imminent arrest during your crazy time, but we gotta move.