- Climate Feedback: Greenhouse history revealed
"The Earth’s greenhouse history of the last 800,000 years is an open book now, thanks to years of detective work by two large international teams of climate scientists. Nature has two papers this week, here and here, about the levels of atmospheric concentration of the two main greenhouse gases – carbon dioxide and methane – as derived from air entrapped in the EPICA Dome C ice core from Antarctica. Here is an editor's summary.
The first and foremost results: The present day concentration of both gases is higher than has ever been the case in the past 800,000 years. Also, the ups and downs in carbon dioxide and methane curves follows the succession of cold glacial climates and relatively warm periods (such as ours) in between.
... During most of the Earth’s history greenhouse gas concentrations have fluctuated in the absence of humans burning coal and other fossil fuels. But the unprecedented rise of greenhouse gases in the modern atmosphere, to concentrations which threaten to unhinge vital components of the Earth’s climate system, is clearly the result of human activity. In the past, greenhouse gas concentrations have varied owing to subtle feedbacks between orbital changes and oceanic and terrestrial carbon cylcles. Carbon dioxide concentrations depend on oceanic uptake, whereas methane is linked with the size and distribution of wetlands releasing the gas..."
- Climate Policy: From ‘Know How’ to ‘Do Now’ - CommonDreams.org
"... A better question for determining public policy is simpler: “Can we continue to emit increasing amounts of greenhouse gases without provoking unacceptable climate change?” Scientists overwhelmingly agree the answer is no. The basic scientific principles and findings are very clear. Focusing on them creates a world of relative certainty for policy. To draw a parallel, if you jump out of an airplane you need a crude parachute more than an accurate altimeter. And if you take an altimeter, don’t become so bemused tracking your descent that you forget to pull the ripcord.
The next question we should ask is, “What causes us to emit ever more carbon dioxide?” It’s the same thing that causes us to make more of all kinds of wastes: our irrational commitment to economic growth forever on a finite planet.
If we overcome our growth idolatry, we can then ask, “How do we design and manage an economy that respects the limits of the biosphere so economy and biosphere both will survive?” But we are so fixated on maintaining an ever-growing economy that we instead ask, “By how much will we have to increase efficiency to maintain growth in gross domestic product?” Suppose we answer, “By doubling efficiency,” and succeed. So what? We will then just do more of all the things that have become more efficient and therefore cheaper, and will then emit more wastes, including greenhouse gases.
A policy of “efficiency first” does not give us “frugality second” — it makes frugality less necessary. But if we go for “frugality first” — sustainability first — with a national tax on carbon, then we will get “efficiency second” as an adaptation to more expensive carbon fuels.
Efficiency cannot abolish scarcity, despite what politicians say, but it can make scarcity less painful. We must throw out our assumption that economic expansion is always good. There is much evidence that GDP growth at the margin in the United States is uneconomic growth, growth that increases social and environmental costs faster than it increases production benefits.
.... What we need is a stiff severance tax on carbon as it emerges from the well and mine. Besides discouraging everyone’s use of climate-altering fossil fuels, this would enable us to raise enough tax dollars to replace regressive taxes on low incomes. Let’s tax the raw material, not the value added to it by processing and manufacturing. Higher input prices bring efficiency at all subsequent stages of production, and limiting depletion ultimately limits pollution. ... "
- Climate Progress » Blog Archive » Must read: Bush DOE says wind can be 20% of U.S. power by 2030 — with no breakthroughs
"The Bush administration has signed off on a stunning new report, “20% Wind Energy by 2030: Increasing Wind Energy’s Contribution to U.S. Electricity Supply.” ... here are the key conclusions of what is easily the most comprehensive."
- Climate Progress » Blog Archive » Hadley Center to deniers: We are STILL warming
"...the 8 warmest years in the 150 global temperature record are, according to the Hadley Center, in order, 1998, 2005, 2003, 2002, 2004, 2006, and 2007. After the Hadley folk wrote a bunch of essays debunking standard denier myths (see here and below), they actually felt compelled to publish another piece on April 29 (here), pointing out again: The global climate is currently being influenced by the cold phase of this oscillation, known as La Niña (see Expert speaks on La Niña). The current La Niña began to develop in early 2007, having a significant cooling effect on the global average temperature.
Despite this, 2007 was one of the ten warmest years since global records began in 1850 with a temperature some 0.4 °C above average. Indeed, the years 2001-2007 recorded an average of 0.44 °C above the 1961-90 average, which is 0.21 °C warmer than corresponding values for the years 1991-2000. ... [Hadley doesn’t even mention we are at a temporary solar irradiance minimum, which subtracts “no more than about 0.1°C,” according to NASA (see “Hansen throws cold water on cooling climate claim.”)]"
- Open the Future: Feedback, Tipping Points, and Hard Choices
"And if we're too late, millions, perhaps billions, of people will die. I will not accept the loss of so many lives as the only alternative to political leaders in the US and China getting their acts together. Depopulation is not a global warming strategy. It's a horrific, tragic result of the failure of strategy, the failure of imagination, and the failure of our capacity to fight to the last breath for our future."
- Survey: Climate Scientists Agree on Global Warming, Mistrust of Media SolveClimate.com
"The results of the Statistical Assessment Service’s (STATS) survey of 489 climate scientists were just announced. And they highlight the triumph of scientific reason over climate denialism. Again. Yep, it was no surprise that 97% of the scientists polled agreed that global average temps have shot up during the last century -- and that 84% said "human-induced warming" is happening. Meanwhile, three-quarters said that “currently available scientific evidence” substantiates its occurrence.
At least one thing was made clear: Climate science -- and its scientists -- have come a long way since 1991, the last time a survey on the scientific opinion of global warming was taken. Back then only 60% believed that average global temps were up at all, compared with today's 97 percent. And just 41 percent said that current scientific evidence "substantiates the occurrence of human-induced warming."
Today, it's double that number. Interestingly, the survey also revealed another consensus that has emerged in the last 17 years: a total distrust from scientists of the mainstream media's coverage of climate change. Below are the numbers: Only 1% of climate scientists rate either broadcast or cable television news about climate change as “very reliable.” Another 31% say broadcast news is "somewhat reliable," compared to 25% for cable news. (The remainder rate TV news as "not very" or "not at all" reliable.) Local newspapers are rated as very reliable by 3% and somewhat reliable by 33% of scientists. Even the national press (New York Times, Wall St. Journal etc) is rated as very reliable by only 11%, although another 56% say it is at least somewhat reliable. And can you really blame them? (More here and here.)"
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