Re: 'Earthshine' fall heats global warming debate

From: Roger Coppock (rcoppock_at_adnc.com)
Date: 06/03/04 

Date: 3 Jun 2004 15:47:37 -0700

steve <steve@nospam.net> wrote in message news:<hAbvc.169$4Z.65911@news.uswest.net>...
> Roger posted this one a while back with out a response.
>
> So what is the earth's albedo?
>
> a) 29%
> b) 30%
> c) 31%
> d) 32%
> e) 32.4%
> f) all of the above
> g) who knows?
> h) doesn't matter because it's fairly constant.
>
>

I would go here to answer your question:
http://ingrid.ldeo.columbia.edu/SOURCES/.NASA/.ERBE/

>
>
> Roger Coppock wrote:
> > 19:00 27 May 04
> > NewScientist.com news service
> >
> > A new study of earthshine, the sunlight reflected back onto the Moon
> > from our planet, suggests that falling cloud cover could explain the
> > warming of the Earth's lower atmosphere seen over the last 20 years.
> >
> > The idea presents a highly controversial alternative to most
> > scientists' prime suspect for the warming - rising levels of
> > greenhouse gases. However, although other researchers say the
> > technique could produce useful data in the future, they argue the
> > current study is simply not strong enough to draw meaningful
> > conclusions.
> >
> > The new study, published in Science, was conducted by Enric Palle and
> > colleagues at the Big Bear Solar Observatory in California and the
> > California Institute of Technology in Pasadena. They report that the
> > brightness of earthshine decreased steadily during the period 1984 to
> > 2000, although that trend appears to have reversed since.
> >
> > The decline suggests fewer clouds, which reflect sunlight, and
> > therefore that more sunlight has been making it into the lower
> > atmosphere (troposphere). That change is "consistent with the large
> > tropospheric warming that has occurred over the most recent decades",
> > they write.
> >
> > Why cloud cover should have thinned is "the big question that no-one
> > knows how to answer," says Palle. "We associate it with natural
> > climate variability, but that's really another way of saying we don't
> > know."
> >
> >
> > Pinch of salt
> >
> > However, Bruce Wielicki from the NASA Langley Research Centre in
> > Hampton, Virginia, says that a link between earthshine and
> > tropospheric warming "cannot be concluded or even implied from these
> > results". And John Harries, an expert in earth observation at Imperial
> > College in London, UK, recommends taking the study's conclusions "with
> > a pinch of salt".
> >
> > Wielicki leads the science team of a mission called CERES - the Clouds
> > and the Earth's Radiant Energy System - which has instruments on three
> > satellites measuring both the amount of visible light reflected by the
> > Earth and the amount of infrared radiation it is emitting.
> >
> > Without measuring both, he explains, you cannot infer anything about
> > warming. CERES data, for example, show that clouds not only reflect
> > lots of visible light, they also act like a blanket and trap infrared
> > radiation in the lower atmosphere. The two effects almost cancel out,
> > so there is little overall change in the energy the atmosphere
> > retains.
> >
> > A further objection is that direct telescope measurements of
> > earthshine in Palle's study only start in 1998. The data for the
> > previous 14 years is based on . . .
> >
> > The rest of this article is at:
> > http://www.newscientist.com/news/news.jsp?id=ns99995048

Relevant Pages

  • Solar Physicists Report Paradox in Eos: Less Sunlight, But Temps Rise (Forwarded)
    ... NJIT Solar Physicists Report Paradox in Eos: Less Sunlight, ... This large variability of the clouds and albedo ... Goode is the director of Big Bear Solar Observatory, California, where the ... that the Earth may continue warming, ...
    (sci.space.news)
  • Solar Physicists Report Paradox in Eos: Less Sunlight, But Temps Rise (Forwarded)
    ... NEWARK -- Less sunlight reaching the Earth's surface has not translated into cooler temperatures, according to a team of solar physicists at New Jersey Institute of Technology. ... The scientists, who monitor the Earth's reflectance by measuring what is known as the moon's earthshine, have observed that the amount of light reflected by Earth -- its albedo -- has increased since 2000. ... The scientists find that the seemingly paradoxical result is due to an increase in the cloud cover coupled with a peculiar re-arrangement of the clouds, but are unsure why this is happening. ...
    (sci.astro)
  • Re: Global warming test!
    ... A researcher in Israel had been measuring the amount of sunlight ... researchers measured sunlight in the eastern Indian ocean, ... opacity of the atmosphere. ... The dust emitted is much finer than natural dust, ...
    (rec.motorcycles)
  • in case you need something big to worry about
    ... Baffled Scientists Say Less Sunlight Reaching Earth Robert Roy Britt ... "The data also reveal that from 2000 to now the clouds have changed so ...
    (soc.retirement)
  • Solar Physicists Report Paradox in Eos: Less Sunlight, But Temps Rise (Forwarded)
    ... NEWARK -- Less sunlight reaching the Earth's surface has not translated into cooler temperatures, according to a team of solar physicists at New Jersey Institute of Technology. ... The scientists, who monitor the Earth's reflectance by measuring what is known as the moon's earthshine, have observed that the amount of light reflected by Earth -- its albedo -- has increased since 2000. ... The scientists find that the seemingly paradoxical result is due to an increase in the cloud cover coupled with a peculiar re-arrangement of the clouds, but are unsure why this is happening. ...
    (sci.geo.meteorology)