The new normal
- 14 Sep 2011, 00:00
- Neil Roberts
"All weather events are now influenced
by climate change because all weather now develops in a different
environment than before."
With this great line Dr. Richard Somerville from the new
Climate Communication project summarised the position now taken
by many climate scientists, traditionally wary of linking extreme
weather events with climate change.
Somerville, professor Emeritus of Scripps Institution of
Oceanography and science director of Climate
Communication, went on:
"Some types of extreme weather events
are becoming more frequent and or severe due to climate change,
heat waves, heavy rain, floods, and droughts among them. Climate
change is increasing the odds that extreme weather will occur."
Climate Communication labels itself as a "non-profit
science and outreach project". It was launched last month by a
group of respected
climate scientists and science
communication staff and is funded by the Rockerfeller Brothers
Fund and the ClimateWorks Foundation It is
headed by Director Susan Joy Hassol, a climate change
communicator, analyst, and author; Dr Somerville is the project's
science director. Its science
advisers include Jeff Masters of the Weather
Underground, Bob Corell, chair of the Arctic Climate Impact
Assessment, and Greg Holland, chair of the Regional Climate
Prediction Program at the National Center for Atmospheric Research.
Hassol has outlined more about the project in a
guest post at Climate Progress.
With extreme weather events hardly out of the news in recent
weeks, Climate Communication's press conference last week
Their overview of the subject makes the point:
"Recent weather events such as deadly
heat waves and devastating floods have sparked popular interest in
understanding the role of global warming in driving extreme
weather. These events are part of a new pattern of more extreme
weather across the globe, shaped in part by human-induced climate
They go on:
"Rigorous analyses have shown that
natural variability alone cannot explain the observed long-term
trends of changing extremes in temperature and precipitation.
"In contrast, the observed trends fit well with our understanding
of how climate change drives changes in weather. Computer models of
the climate that include both natural forces as well as human
influences are consistent with observed global trends in heat
waves, warm days and nights, and frost days over the last four
decades. Human influence has also been shown to have contributed to
the increase of heavy precipitation over the Northern
"Extreme weather events do not have a single cause but instead
have various possible contributing factors - and human-induced
climate change is now one of those factors."
Kelly Rigg, of the Global Campaign for Climate Action,
writing at Huff Post recently argued:
"It's time to change the terms of this
fruitless debate. When asked whether an extreme weather event is
caused by climate change, scientists should reframe the debate by
rephrasing the question: "Are more events like this what you would
expect in a warming world?" The answer would be a resounding
This discussion has been particularly live in the US recently.
There were the hurricanes - Irene and Katia - and the
drought and wildfires across Texas and other US states, that
have all added to the United States' sense of "
However, as Jules Boykoff at
Comment is Free wrote last week:
"But recent record-breaking
"meteorological misery" from coast to coast is making it clear that
severe weather may well be the new normal. Weather is getting more
extreme and this, scientists tell us, has a lot to do with climate
change. Meanwhile, inside the Beltway and among mainstream
media, there's virtually no public debate about the likelihood
we're already paying the high price of climate change."
Meanwhile, in Pakistan five million people have been affected by
floods in Baluchistan and Sindh.
Climate Signals reported "900 villages have been submerged and
about 100,000 homes have been completely destroyed."
a Reuters piece noted last week, scientists have traditionally
been cautious about linking extreme weather events with climate
change. It is not possible to directly link any particular event
with the effects of the changing climate - but
as this from Climate Centralshows, scientists are becoming more
willing to say that climate change is making the extreme weather we
are experiencing now more likely:
"Seager [Columbia University Lamont
Doherty Earth Observatory] climate change, driven by increasing
amounts of greenhouse gases in our atmosphere, is tilting the
scales in favor of future droughts that may look like this
research from Boston University, published in Climate Change
Letters journal, has
attracted attention. The research estimated the impact
near-term increases in global temperatures will have on summertime
temperatures in the U.S. and around the globe and concluded
"substantial fractions of the globe
could experience seasonal-mean temperature extremes with high
regularity, even if the global-mean temperature increase remains
below the 2°C target."
Guardian leader picked up on that same research. The paper
quoted climate secretary Chris Huhne's warning that we face
"unprecedented environmental and geopolitical catastrophe". Huhne,
the Guardian says, is right to issue his warning. But, echoing the
points made by Boycoff: "There is no great evidence that fellow
politicians are listening very intently."