"We believe the claims by NASA and (Goddard Institute for Space Studies), that man-made carbon dioxide
is having a catastrophic impact on global climate change are not
substantiated," write the 49 signatories in a letter to NASA
administrator Charles Bolden. [Read the Full Letter]
This is the most recent objection by skeptics who challenge the reality
of human-caused global warming. For decades, climate scientists have
warned that humans are changing the composition of our atmosphere,
warming the planet and, as a result, face rising sea levels, more extreme weather
and other consequences. The concept is now well established in
scientific literature and attempts to address it are the subject of
ongoing international talks.
The letter originates from members of the Johnson Space Center Chapter
of the NASA Alumni League, according to Walter Cunningham, a former
astronaut who flew the Apollo 7 in 1968 and one of the letter's signatories.
In its four paragraphs, the letter deliberately avoids delving into its
signatories' reasons for doubting climate-change science, Cunningham
told LiveScience. "It's really trying to get NASA to back off from
taking political positions on science." [10 Climate Change Myths Busted]
Human-caused global warming is "a very open issue right now," he said.
However, that is not how the scientific establishment sees it. NASA
Chief Scientist Waleed Abdalati responded to the letter to say that if
the work
of NASA scientists — who may use the agency's space-based observation
tools to study climate change — withstands the scrutiny of other
scientists through peer review, then it encourages them to share their
results with the public.
"If the authors of this letter disagree with specific scientific
conclusions made public by NASA scientists, we encourage them to join
the debate in the scientific literature or public forums rather than
restrict any discourse," Abdalati said in the statement.
For his part, Cunningham said the peer-review process — in which
scientists in relevant fields scurtinize research — Abdalati mentions is
rigged against those who challenge the standard view of global warming.
In spite of its wide acceptance among climate scientists and the scientific community, global-warming skeptics
include some scientists. For instance, William Happer, a physicist from
Princeton University who is not involved in the NASA letter, recently
penned an editorial to the Wall Street Journal stating that the world
has not warmed as the concept of carbon dioxide-driven global warming
predicts it would.
Like Happer, Cunningham has a background in physics, he is not a
climate scientist. According to his NASA astronaut profile, Cunningham
has a master's in physics from the University of California, Los
Angeles, and completed doctoral work as well. Of the 46 signatories who
listed their positions, eight are astronauts and others identify
themselves as having worked in a variety of positions, including within
NASA's science or engineering directorates.
The letter calls out the leadership of NASA's Goddard Institute for Space Studies (GISS) in New York, which is headed by James Hansen, a high-profile climate scientist,
who has been an important force propelling the prospect of
catastrophic, human-caused climate change into the public eye. Recently,
Hansen has increasingly turned to activism, and was arrested at a
protest in August. Hansen could not be reached for comment by deadline.
Gavin Schmidt, also a climate scientist at GISS, takes issue with
statements by global warming skeptics, such as, "It is clear that the
science is NOT settled," as the letter reads.
"Dealing with the future always involves dealing with uncertainty — and
this is as true with climate as it is with the economy," Schmidt writes
in a post at RealClimate.org.
"Science has led to a great deal of well-supported concern that
increasing emissions of CO2 (in particular) are posing a substantial
risk to human society."
Among those who study climate, issues such as the existence of the greenhouse effect,
increasing atmospheric carbon dioxide and other greenhouse gases over
the past century, their human origin, and warming over the 20th century
are no longer subject to fundamental debate, he writes.
The claims in the letter are too vague to be clear, Schmidt told
LiveScience in an email, but "If any of signatories are ever in New
York, I would be happy to discuss with them the science that gets done
at GISS."
Wynne Parry, LiveScience Senior Writer@LiveScience.com
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