We Just Passed the Climate’s “Grim Milestone”

Source: Mother Jones

Authors: Tim McDonnell, and James West

Over the last couple weeks, scientists and environmentalists have been keeping a particularly close eye on the Hawaii-based monitoring station that tracks how much carbon dioxide is in the atmosphere, as the count tiptoed closer to a record-smashing 400 parts per million. Yesterday, we finally got there: The daily mean concentration was higher than at any time in human history, NOAA reported today.

Don’t worry: The earth is not about to go up in a ball of flame. The 400 ppm mark is only a milestone, 50 ppm over what legendary NASA scientist James Hansen has since 1988 called the safe zone for avoiding the worst impacts of climate change, and yet only halfway to what the IPCC predicts we’ll reach by the end of the century.

“Somehow in the last 50 ppm we melted the Arctic,” said environmentalist and founder of activist group 350.org Bill McKibben, who called today’s news a “grim but predictable milestone” and has long used the symbolic number as a rallying call for climate action. “We’ll see what happens in the next 50.”

We could find out soon enough: With the East Coast still recovering from Superstorm Sandy and the West gearing up for what promises to be a nasty fire season, University of California ecologist Max Moritz says milestones like these are “an excuse for us to take a good hard look at where we are,” especially as the carbon concentration shows no signs of reversing course.

Scientists first saw the carbon scale tip past 400 ppm last summer, but only briefly; the record reported today by NOAA is the first time a daily average has surpassed that point. For the last several years concentrations have hovered in the 390s, and we’re still not to the point where the carbon concentration will stay above the 400 ppm threshold permanently. But that’s just around the corner, said J. Marshall Shepherd, president of the American Meteorological Society.

“It’s clear that sometime next year we’ll see 400 consistently,” he said. “Avoiding the future warming will require a large and rapid reduction in greenhouse gases.

Most scientists, environmentalists, and climate-conscious policymakers agree this will require, at a minimum, slashing the use of fossil fuels, and in the meantime, taking steps to adapt for a world with higher temperatures, higher seas, and more extreme weather. For example, according to Hansen, the world will need to completely stop burning coal by 2030 if returning to 350 ppm is to remain possible. What’s the holdup? Texas Tech climatologist Katherine Hayhoe blames “the inertia of our economic system, and the inertia of our political system.” But she, like most of her peers, believe it can—and must—be done: “We have to change how we get our energy and how we use our energy.”

Some progress is being made on that front: Thanks to energy efficiency gains, increased use of renewable power, and policies to cut emissions from cars and power plants, carbon emissions in the US have fallen 13 percent in the last seven years. But they’re expected to begin climbing again soon, and worldwide, 2012 saw the most carbon emissions ever. Today’s milestone underscores the reality that if we’re serious about addressing climate change, there’s still a long road ahead.

“So far we have failed miserably in tackling this problem,” NOAA scientist Pieter Tans, who oversees the monitoring program, told the Times.

For McKibben, the real date to mark in the history books has yet to arrive: “I don’t think this will be the turning point. The turning point will be when we do something about it.”

Emphasis Mine

see: http://www.motherjones.com/blue-marble/2013/05/we-just-passed-climates-grim-milestone

Greenhouse Gases Hit Record Levels; Concentrations Exceed Scientists’ Worst-Case Scenarios

N.B.: If the religious right had not discredited science in the USA, we would have taken action years ago…

From:HuffPost

“GENEVA — Global warming gases have hit record levels in the world’s atmosphere, with concentrations of carbon dioxide up 39 percent since the start of the industrial era in 1750, the U.N. weather agency said Monday.

The new figures for 2010 from the World Meteorological Organization show that CO2 levels are now at 389 parts per million, up from about 280 parts per million a quarter-millenium ago. The levels are significant because the gases trap heat in the atmosphere.

WMO Deputy Secretary-General Jeremiah Lengoasa said CO2 emissions are to blame for about four-fifths of the rise. But he noted the lag between what gets pumped into the atmosphere and its effect on climate.

“With this picture in mind, even if emissions were stopped overnight globally, the atmospheric concentrations would continue for decades because of the long lifetime of these greenhouse gases in the atmosphere,” he said.

Negotiators from virtually all the world’s nations will gather later this month in South Africa to try to agree on steps to head off the worst of the climate disruptions that researchers say will result if concentrations hit around 450 parts per million.

That could happen within several decades at the current rate, though some climate activists and vulnerable nations say the world has already passed the danger point of 350 parts per million and must somehow undo it.

The WMO said the increase of 2.3 parts per million in CO2 in the atmosphere between 2009 and 2010 shows an acceleration from the average 1.5 parts per million increase during the 1990s.

But there are seasonal fluctuations, too. During the summer growing season, plants absorb carbon dioxide from the atmosphere. In winter, the concentration of C02 rises as vegetation and other biomass decompose.

Since 1750, WMO says, atmospheric concentrations of CO2 have risen 39 percent, those of nitrous oxide have gone up 20 percent and concentrations of methane jumped 158 percent.

Its report Monday cites fossil fuel-burning, loss of forests that absorb CO2 and use of fertilizer as the main culprits.”

Emphasis Mine

see:http://www.huffingtonpost.com/2011/11/21/greenhouse-gases-record-levels_n_1104773.html?ref=daily-brief?utm_source=DailyBrief&utm_campaign=112111&utm_medium=email&utm_content=NewsEntry&utm_term=Daily%20Brief