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Janerik Larsson

Janerik Larsson

Jag har några gånger anspelat på Naomi Kleins nya bok där ”klimatfrågan” påstås kunna lösas med global planhushållning. Det är strunt, men många människor undrar ändå om vad vi egentligen vet eller inte vet om interaktionen mellan frågan om global uppvärmning å ena sidan och politiska ingrepp av olika slag å den andra.

Idag har Wall Street Journal en intressant artikel i ämnet. Författare till den är Steven E. Koonin  som presenteras så: He was undersecretary for science in the Energy Department during President Barack Obama’s first term and is currently director of the Center for Urban Science and Progress at New York University. His previous positions include professor of theoretical physics and provost at Caltech,

Han skriver:

The idea that ”Climate science is settled” runs through today’s popular and policy discussions. Unfortunately, that claim is misguided. It has not only distorted our public and policy debates on issues related to energy, greenhouse-gas emissions and the environment. But it also has inhibited the scientific and policy discussions that we need to have about our climate future.

My training as a computational physicist—together with a 40-year career of scientific research, advising and management in academia, government and the private sector—has afforded me an extended, up-close perspective on climate science. Detailed technical discussions during the past year with leading climate scientists have given me an even better sense of what we know, and don’t know, about climate. I have come to appreciate the daunting scientific challenge of answering the questions that policy makers and the public are asking.

The crucial scientific question for policy isn’t whether the climate is changing. That is a settled matter: The climate has always changed and always will. Geological and historical records show the occurrence of major climate shifts, sometimes over only a few decades. We know, for instance, that during the 20th century the Earth’s global average surface temperature rose 1.4 degrees Fahrenheit.

Nor is the crucial question whether humans are influencing the climate. That is no hoax: There is little doubt in the scientific community that continually growing amounts of greenhouse gases in the atmosphere, due largely to carbon-dioxide emissions from the conventional use of fossil fuels, are influencing the climate. There is also little doubt that the carbon dioxide will persist in the atmosphere for several centuries. The impact today of human activity appears to be comparable to the intrinsic, natural variability of the climate system itself.

Rather, the crucial, unsettled scientific question for policy is, ”How will the climate change over the next century under both natural and human influences?” Answers to that question at the global and regional levels, as well as to equally complex questions of how ecosystems and human activities will be affected, should inform our choices about energy and infrastructure.

But—here’s the catch—those questions are the hardest ones to answer. They challenge, in a fundamental way, what science can tell us about future climates.

I sin långa artikel pekar han sedan på helt funamentala faktorer – t ex kunskap om världshaven – som gör att man idag inte kan avgöra vad som är möjligt att påverka och vad som inte kan påverkas genom mänskligt beteende.

We often hear that there is a ”scientific consensus” about climate change. But as far as the computer models go,there isn’t a useful consensus at the level of detail relevant to assessing
human influences.

While the past two decades have seen progress in climate science, the field is not yet mature enough to usefully answer the difficult and important questions being asked of it. This decidedly unsettled state highlights what should be obvious: Understanding climate, at the level of detail relevant to human influences, is a very, very difficult problem.

Det är inte bara Naomi Klein som har en politisk agenda som i grunden helt struntar i vad vi vet eller inte vet om klimatförändringar. Det kommer att debatteras mycket om detta framöver. Koonins artikel är ett viktigt bidrag som belyser den osäkerhet som råder.

Jag är ju ingen klimatexpert, men det behövs ju inte några stora kunskap för att genom att se bakåt konstatera att världens klimat dramatiskt förändrats tidigare.

 

Om gästbloggen

Janerik Larsson är gästbloggare hos SvD Ledare. Han är skribent, författare och journalist, verksam i Stiftelsen Fritt Näringsliv och pr-byrån Prime. Bloggar om svensk politik och har en internationell utblick mot främst brittiska och amerikanska medier.
Åsikter är hans egna.
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