The truth about global warming
- it's the Sun
that's to blame
By Michael Leidig and Roya Nikkhah
Global warming has
finally been explained: the Earth is getting hotter because the sun is
burning more brightly than at any time during the past 1,000 years,
according to new research.
A study by Swiss and German scientists suggests that increasing
radiation from the sun is responsible for recent global climate
changes.
Dr. Sami Solanki, the director of the renowned Max Planck Institute
for Solar System Research in Gottingen, Germany, who led the research,
said:
"The sun has been at its strongest over the past 60 years, and may
now be affecting global temperatures."
"The sun is in a changed state. It is brighter than it was a few
hundred years ago and this brightening started relatively recently -
in the last 100 to 150 years."
Dr. Solanki said that the brighter sun and higher levels of
"greenhouse gases," such as carbon dioxide, both contributed to the
change in the Earth's temperature, but it was impossible to say which
had the greater impact.
Average global temperatures have increased by about 0.2 degrees
Celsius over the past 20 years, and are widely believed to be
responsible for new extremes in weather patterns. After pressure from
environmentalists, politicians agreed to the Kyoto Protocol in 1997,
promising to limit greenhouse gas emissions between 2008 and
2012. Britain ratified the protocol in 2002, and said it would cut
emissions by 12.5 percent from 1990 levels.
Globally, 1997, 1998, and 2002 were the hottest years since
worldwide weather records were first collated in 1860.
Most scientists agree that greenhouse gases from fossil fuels have
contributed to the warming of the planet in the past few decades, but
have questioned whether a brighter sun is also responsible for rising
temperatures.
To determine the sun's role in global warming, Dr. Solanki's
research team measured magnetic zones on the sun's surface, known as
sunspots, which are believed to intensify the sun's energy output.
The team studied sunspot data going back several hundred
years. They found that a dearth of sunspots signalled a cold period -
which could last up to 50 years - but that over the past century, their
numbers had increased as the Earth's climate grew steadily warmer. The
scientists also compared data from ice samples collected during an
expedition to Greenland in 1991. The most recent samples contained the
lowest recorded levels of beryllium 10 for more than 1,000 years.
Beryllium 10 is a particle created by cosmic rays, that decreases in
the Earth's atmosphere as the magnetic energy from the sun increases.
Scientists can currently trace beryllium 10 levels back 1,150 years.
Dr. Solanki does not know what is causing the sun to burn brighter
now, or how long this cycle will last.
He says that the increased solar brightness over the past 20 years
has not been enough to cause the observed climate changes, but believes
that the impact of more intense sunshine on the ozone layer and on
cloud cover could be affecting the climate more than the sunlight
itself.
Dr. Bill Burrows, a climatologist and a member of the Royal
Meteorological Society, welcomed Dr. Solanki's research. He said:
"While the established view remains that the sun cannot be
responsible for all the climate changes we have seen in the past 50
years or so, this study is certainly significant."
"It shows that there is enough happening on the solar front to
merit further research. Perhaps we are devoting too many resources to
correcting human effects on the climate, without being sure that we are
the major contributor."
Dr. David Viner, the senior research scientist at the University of
East Anglia's climatic research unit, said the research showed that
the sun did have an effect on global warming.
He added, however, that the study also showed that over the past 20
years, the number of sunspots had remained roughly constant, while the
Earth's temperature had continued to increase.
This suggested that over the past 20 years, human activities such
as the burning of fossil fuels and deforestation had begun to dominate
"the natural factors involved in climate change", he said.
Dr. Gareth Jones, a climate researcher at the Met Office, said that
Dr. Solanki's findings were inconclusive, because the study had not
incorporated other potential climate change factors.
"The sun's radiance may well have an impact on climate change, but
it needs to be looked at in conjunction with other factors, such as
greenhouse gases, sulphate aerosols, and volcano activity," he said.
The research adds weight to the views of David Bellamy, the
conservationist. "Global warming - at least the modern nightmare
version - is a myth," he said. "I am sure of it, and so are a growing
number of scientists. But what is really worrying is that the world's
politicians and policy-makers are not."
"Instead, they have an unshakeable faith in what has,
unfortunately, become one of the central credos of the environmental
movement: humans burn fossil fuels, which release increased levels of
carbon dioxide - the principal so-called greenhouse gas - into the
atmosphere, causing the atmosphere to heat up. They say this is global
warming: I say this is poppycock."
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