Climate Change - a climate scientists perspective

The Terramar Organics Newsletter, January/February 2007

Welcome to this month's newsletter - enjoy and please feel free, as always, to send us your comments.

Many thanks to Benedict Reinardy for the following contribution to the discussion on climate change:

 

Climate change - a climate scientists perspective

Climate change is now an accepted fact in nearly all the scientific community however it is important to know what evidence is being used to come to these conclusions and also the uncertainties which still exist (there are many!).

 

Looking at the past to put the present in context

A large part of the global warming argument focuses on the difficulties in separating anthropogenic from natural climate change. One way to tackle this problem is too look at past climate change and compare it to what is taking place today. Rapid climate change has been a factor in Earth's recent geological history. The planet has alternated back and forth between ice ages and warm periods, good evidence of which dates back to at least the last 1.6 million years. What drives this process is mainly the way the Earth orbits the Sun which varies in a cyclic manner over time. If we look at the last time the Earth orbited the sun as it does now and look at the inferred temperature and C02 records, we know that back then they were significantly lower (see Ruddiman, 2005).

 

Sea Level

Rising sea levels present a great danger to everyone living in coastal areas, even a few centimetres would have serious consequences during extreme events such as storm surges. There is good evidence that the Greenland Ice Sheet is now melting at an increasing rate (see Chen et al. 2006). The destructing of this ice sheet would lead to a 7m global sea level rise and it looks as if the West Antarctic Ice Sheet is going the same way which would lead to a further 5m rise.

 

Glacier retreat

Mountain glaciers in other parts of the world are a sensitive indicator of climate change and in nearly all cases they have been retreating in the last 10-20 years. In many parts of the world glaciers provide an essential source of fresh water. In 20-30 years it is highly probable that glaciers in tropical regions (such as the one on the top of Kilimanjaro) will no longer exist.

 

Ocean circulation

Ocean circulation governs a large part of the Earth climate system because it is the biggest transporter of heat, most of which flows from the tropics to higher latitudes as well as drawing cooler water from the poles. Many Earth processes are threshold systems whereby a critical level is reached followed in most cases by sudden rapid change. Recently much attention has been placed on North Atlantic circulation and the effect its slow down would have on the climate here in the UK. There is now evidence that this Atlantic conveyor belt transporting warm tropical waters up towards Scandinavia where it cools, sinks and travels back south at depth, has now slowed by 30% (Bryden et al., 2005). The concern is that this circulation could cease suddenly when a critical level is reached as it has done in the past, and lead to catastrophic climate change across northwest Europe at least.

 

Note of caution

While climate change is now a reality there is still a large amount of uncertainty as to the exact effect and magnitude these changes will have. It should also be recognised that there is some evidence, particularly at a local scale, of climate cooling and of climate having been warmer than today in the recent past (last 12,000yrs).

 

References

Bryden, H. L; Longworth, H. R. and Cunningham, S. A. 2005. Slowing of the Atlantic meridional overturning circulation at 25 N. Nature, 4381, 566-657.

Chen, J. L.; Wilson, C. R. and Tapley, B. D. 2006. Satellite gravity measurements confirm accelerated melting of Greenland Ice Sheet. Science, 313, 1958-1960.

Ruddiman, W.F. (2005). Cold climate during the closest stage 11 analog to recent millennia. Quaternary Science Reviews 24, 1111-1121.

Benedict Reinardy
Glaciology Group
Department of Geography
University of Wales Swansea
Singleton Park
Swansea SA2 8PP
+44 (0)1792 602091 (phone)
+44 (0)1792 295955 (fax)

 

International Polar Year 2007-2008

Critical to the study of climate change are the ice caps of the Arctic and Antarctic. Research projects will be carried out over the next two years as part of the International Polar Year to study the changes which are occurring there and to further research into the valuable knowledge which these delicate areas of the planet hold.

Log on to http://www.ipy.org for further information.

 

Free Energy

Considering the effect humans can have on climate change, it is interesting to note that there is a considerable wealth of knowledge and research on Free Energy (perpetual motion machines) and ways in which it can be harnessed.

The benefit of free energy being that it is ultimately a sustainable energy source which is relatively cheap in both economic and environmental terms.

An Irish company, Steorn (http://www.steorn.net), claims to have already developed a technology which produces free, clean and constant energy. Claims to this effect have been made for hundreds of years, but for one reason or another (Google the topic for an idea of the depth of discussion out there), none of these claims have come to fruition. Nevertheless, the laws of physics are always up for a challenge and so perhaps, one day, we will indeed have a perpetual motion technology which can help cut our rising emissions and therefore limit the damage done to the global climate.

 

On a local note Road Sense! - cyber action

A large road project: the AWPR (Aberdeen Western Peripheral Route) is being planned to cut through swathes of Aberdeen green belt all in the name of development. The Road Sense campaign group is set up in order to seek support for and to promote a more sustainable transport option for the Aberdeen area.
Log on to http://www.road-sense.org for further information on the project.

The road orders have now been published and anyone (no matter where you live) who wishes to object to the proposals should do so by the 9th of February at the Road Sense website or by writing to Transport Scotland, as detailed on the Road Sense website.

Terramar Organics fully supports the development of transport links in the Aberdeen area, but believes that a more sustainable approach must be used with public transport, cycling and pedestrian facility improvements on top of the agenda NOT senseless road building.

 

Lastly, anyone for a breath of fresh air? Read this:
http://news.bbc.co.uk/cbbcnews/hi/newsid_6290000/newsid_6298400/6298483.stm

Best wishes
Peter and Tom

The Terramar Organics Team

 

07999 613 982 | http://www.terramar.co.uk

Help spread the word - tell your friends, relatives and anyone who might be interested about Terramar.

news News

Brown fixes green energy with nuclear
Greenpeace report poll fixing by govt

news Teatime

Two Bills for One
Relax with Bills Bailey and Connolly

blog Blog

Obama wins US election
...and Trump gets go ahead for environmental destruction