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Good news for the earth’s climate system?

Filed under: — group @ 6 February 2010

Guest Commentary by Jim Bouldin (UC Davis)

How much additional carbon dioxide will be released to, or removed from, the atmosphere, by the oceans and the biosphere in response to global warming over the next century? That is an important question, and David Frank and his Swiss coworkers at WSL have just published an interesting new approach to answering it. They empirically estimate the distribution of gamma, the temperature-induced carbon dioxide feedback to the climate system, given the current state of the knowledge of reconstructed temperature, and carbon dioxide concentration, over the last millennium. It is a macro-scale approach to constraining this parameter; it does not attempt to refine our knowledge about carbon dioxide flux pathways, rates or mechanisms. Regardless of general approach or specific results, I like studies like this. They bring together results from actually or potentially disparate data inputs and methods, which can be hard to keep track of, into a systematic framework. By organizing, they help to clarify, and for that there is much to be said.
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The IPCC is not infallible (shock!)

Filed under: — group @ 19 January 2010

Like all human endeavours, the IPCC is not perfect. Despite the enormous efforts devoted to producing its reports with the multiple levels of peer review, some errors will sneak through. Most of these will be minor and inconsequential, but sometimes they might be more substantive. As many people are aware (and as John Nieslen-Gammon outlined in a post last month and Rick Piltz goes over today), there is a statement in the second volume of the IPCC (WG2), concerning the rate at which Himalayan glaciers are receding that is not correct and not properly referenced.
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Unforced variations 2

Filed under: — gavin @ 1 January 2010

Continuation of the open thread. Please use these threads to bring up things that are creating ‘buzz’ rather than having news items get buried in comment threads on more specific topics. We’ll promote the best responses to the head post.

Knorr (2009): Case in point, Knorr (GRL, 2009) is a study about how much of the human emissions are staying the atmosphere (around 40%) and whether that is detectably changing over time. It does not undermine the fact that CO2 is rising. The confusion in the denialosphere is based on a misunderstanding between ‘airborne fraction of CO2 emissions’ (not changing very much) and ‘CO2 fraction in the air’ (changing very rapidly), led in no small part by a misleading headline (subsequently fixed) on the ScienceDaily news item Update: MT/AH point out the headline came from an AGU press release (Sigh…). SkepticalScience has a good discussion of the details including some other recent work by Le Quéré and colleagues.

Update: Some comments on the John Coleman/KUSI/Joe D’Aleo/E. M. Smith accusations about the temperature records. Their claim is apparently that coastal station absolute temperatures are being used to estimate the current absolute temperatures in mountain regions and that the anomalies there are warm because the coast is warmer than the mountain. This is simply wrong. What is actually done is that temperature anomalies are calculated locally from local baselines, and these anomalies can be interpolated over quite large distances. This is perfectly fine and checkable by looking at the pairwise correlations at the monthly stations between different stations (London-Paris or New York-Cleveland or LA-San Francisco). The second thread in their ‘accusation’ is that the agencies are deleting records, but this just underscores their lack of understanding of where the GHCN data set actually comes from. This is thoroughly discussed in Peterson and Vose (1997) which indicates where the data came from and which data streams give real time updates. The principle one is the CLIMAT updates of monthly mean temperature via the WMO network of reports. These are distributed by the Nat. Met. Services who have decided which stations they choose to produce monthly mean data for (and how it is calculated) and is absolutely nothing to do with NCDC or NASA.

Further Update: NCDC has a good description of their procedures now available, and Zeke Hausfather has a very good explanation of the real issues on the Yale Forum.

The Guardian’s Editorial

Filed under: — eric @ 8 December 2009

The following editorial was published today by 56 newspapers around the world in 20 languages including Chinese, Arabic and Russian. The text was drafted by a Guardian team during more than a month of consultations with editors from more than 20 of the papers involved. Like The Guardian most of the newspapers have taken the unusual step of featuring the editorial on their front page. The Guardian, the editorial is free to reproduce under Creative Commons.

RealClimate takes no formal position on the statements made in the editorial.


Copenhagen climate change conference: Fourteen days to seal history’s judgment on this generation

Today 56 newspapers in 45 countries take the unprecedented step of speaking with one voice through a common editorial. We do so because humanity faces a profound emergency.

Unless we combine to take decisive action, climate change will ravage our planet, and with it our prosperity and security. The dangers have been becoming apparent for a generation. Now the facts have started to speak: 11 of the past 14 years have been the warmest on record, the Arctic ice-cap is melting and last year’s inflamed oil and food prices provide a foretaste of future havoc. In scientific journals the question is no longer whether humans are to blame, but how little time we have got left to limit the damage. Yet so far the world’s response has been feeble and half-hearted.

Climate change has been caused over centuries, has consequences that will endure for all time and our prospects of taming it will be determined in the next 14 days. We call on the representatives of the 192 countries gathered in Copenhagen not to hesitate, not to fall into dispute, not to blame each other but to seize opportunity from the greatest modern failure of politics. This should not be a fight between the rich world and the poor world, or between east and west. Climate change affects everyone, and must be solved by everyone.

The science is complex but the facts are clear. The world needs to take steps to limit temperature rises to 2C, an aim that will require global emissions to peak and begin falling within the next 5-10 years. A bigger rise of 3-4C — the smallest increase we can prudently expect to follow inaction — would parch continents, turning farmland into desert. Half of all species could become extinct, untold millions of people would be displaced, whole nations drowned by the sea. The controversy over emails by British researchers that suggest they tried to suppress inconvenient data has muddied the waters but failed to dent the mass of evidence on which these predictions are based.

Few believe that Copenhagen can any longer produce a fully polished treaty; real progress towards one could only begin with the arrival of President Obama in the White House and the reversal of years of US obstructionism. Even now the world finds itself at the mercy of American domestic politics, for the president cannot fully commit to the action required until the US Congress has done so.

But the politicians in Copenhagen can and must agree the essential elements of a fair and effective deal and, crucially, a firm timetable for turning it into a treaty. Next June’s UN climate meeting in Bonn should be their deadline. As one negotiator put it: “We can go into extra time but we can’t afford a replay.”

At the deal’s heart must be a settlement between the rich world and the developing world covering how the burden of fighting climate change will be divided — and how we will share a newly precious resource: the trillion or so tonnes of carbon that we can emit before the mercury rises to dangerous levels.

Rich nations like to point to the arithmetic truth that there can be no solution until developing giants such as China take more radical steps than they have so far. But the rich world is responsible for most of the accumulated carbon in the atmosphere – three-quarters of all carbon dioxide emitted since 1850. It must now take a lead, and every developed country must commit to deep cuts which will reduce their emissions within a decade to very substantially less than their 1990 level.

Developing countries can point out they did not cause the bulk of the problem, and also that the poorest regions of the world will be hardest hit. But they will increasingly contribute to warming, and must thus pledge meaningful and quantifiable action of their own. Though both fell short of what some had hoped for, the recent commitments to emissions targets by the world’s biggest polluters, the United States and China, were important steps in the right direction.

Social justice demands that the industrialised world digs deep into its pockets and pledges cash to help poorer countries adapt to climate change, and clean technologies to enable them to grow economically without growing their emissions. The architecture of a future treaty must also be pinned down – with rigorous multilateral monitoring, fair rewards for protecting forests, and the credible assessment of “exported emissions” so that the burden can eventually be more equitably shared between those who produce polluting products and those who consume them. And fairness requires that the burden placed on individual developed countries should take into account their ability to bear it; for instance newer EU members, often much poorer than “old Europe”, must not suffer more than their richer partners.

The transformation will be costly, but many times less than the bill for bailing out global finance — and far less costly than the consequences of doing nothing.

Many of us, particularly in the developed world, will have to change our lifestyles. The era of flights that cost less than the taxi ride to the airport is drawing to a close. We will have to shop, eat and travel more intelligently. We will have to pay more for our energy, and use less of it.

But the shift to a low-carbon society holds out the prospect of more opportunity than sacrifice. Already some countries have recognized that embracing the transformation can bring growth, jobs and better quality lives. The flow of capital tells its own story: last year for the first time more was invested in renewable forms of energy than producing electricity from fossil fuels.

Kicking our carbon habit within a few short decades will require a feat of engineering and innovation to match anything in our history. But whereas putting a man on the moon or splitting the atom were born of conflict and competition, the coming carbon race must be driven by a collaborative effort to achieve collective salvation.

Overcoming climate change will take a triumph of optimism over pessimism, of vision over short-sightedness, of what Abraham Lincoln called “the better angels of our nature”.

It is in that spirit that 56 newspapers from around the world have united behind this editorial. If we, with such different national and political perspectives, can agree on what must be done then surely our leaders can too.

The politicians in Copenhagen have the power to shape history’s judgment on this generation: one that saw a challenge and rose to it, or one so stupid that we saw calamity coming but did nothing to avert it. We implore them to make the right choice.

Data Sources

Filed under: — group @ 27 November 2009

This page is a catalogue that will be kept up to date pointing to selected sources of code and data related to climate science. Please keep us informed of any things we might have missed, or any updates to the links that are needed.

Climate data (raw)

Climate data (processed)

Paleo-data

Paleo Reconstructions (including code)

Large-scale model (Reanalysis) output

These are weather models which have the real world observations assimilated into the solution to provide a ‘best guess’ of the evolution of weather over time (although pre-satellite era estimates (before 1979) are less accurate).

Large-scale model (GCM) output

These is output from the large scale global models used to assess climate change in the past, and make projections for the future. Some of this output is also available via the Data Visualisation tools linked below.

Model codes (GCMs)

Downloadable codes for some of the GCMs.

Model codes (other)

This category include links to analysis tools, simpler models or models focussed on more specific issues.

Data Visualisation and Analysis

These sites include some of the above data (as well as other sources) in an easier to handle form.

Master Repositories of Climate Data

Much bigger indexes of data sources: