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Burying the hatchet?
In 2001, experts of the Intergovernmental Panel on Climate Change described the current state of the climate. They also came up with predictions
Age creeps up on you unnoticed — the grey hair appear and parts of your body begin to wear out. Climate change is a bit like that — it is slow and we adapt to it. It was only after the Second World War that the realization of human-triggered climate change began to seep into public consciousness.
Industrialization and the internal combustion engine increased the level of carbon dioxide released into the atmosphere and enhanced the greenhouse effect. With time, man-made substances such as the fluorine-based compound used in cooling machinery and plants were implicated. This was found to deplete the ozone layer over the poles, thereby further enhancing and speeding climate change. Natural methane and water vapour also increased the temperature of the atmosphere. There was growing awareness that we were fast destroying our environment.
In 2001, experts of the Intergovernmental Panel on Climate Change (IPCC) described the current state of the climate. They also came up with predictions. The average global temperature was predicted to rise between 1.4-5.8°C by 2100, along with a sea level rise of between 0.09 and 0.88 meters. They also expected changes in extreme weather and climate events including:
1. Higher maximum and minimum temperatures and more hot days over land area (very likely);
2. More intense rainfall (very likely over many areas);
3. Increase in tropical cyclone peak winds and rainfall intensities (likely over some areas);
These predictions come from analysing past data, which is sparse, and from complex computer models, which do not fully capture the total dynamics of this very complicated system. Thus, forecast for the next 10 to 100 years is riddled with uncertainty. And this begins to affect prediction on small spatial scales that are relevant to Pakistan and regions, such as South Asia. These are the most significant current challenges for climate science.
Briefly, this is how the models work. The computer-based models range from “energy balance” models to complex three-dimensional circulation models that calculate the changing weather at over 100,000 points on the globe every 15-30 minutes. The results from these models are compared with climate change observation over the past 50 years. Some large models take nearly three months to run on lightening fast supercomputers to give climatic changes over a much longer period. As with such complex physical systems that are sensitive to initial conditions, even if a model simulates the past reasonably well, this does not mean that it can compute the future accurately.
Climate forecasting is beset with three uncertainties. The first is natural variability, which is studied using identical computer models, but with slightly different starting conditions (data fed into the model to get it started). This is to overcome the “butterfly effect,” which makes the results very sensitive to starting conditions. Second, the different models themselves often give different forecasts and this requires that the model characteristics be tweaked for this variation. Third is the level of future greenhouse gas in the atmosphere. This depends on indeterminate natural factors, such as volcanoes and how society alters its release of gases in response to climate change.
In recent years, a collaborative project on the internet, involving over 70,000 participants from over 130 countries, has created a very large number of climate models. These allow a more comprehensive exploration of possible future climate changes and reduce uncertainty in forecasts. The problem of assessing uncertainty in how climate will respond to current and future greenhouse gas emission is not yet solved, but progress in this is palpable and more reliable probabilistic models are expected to appear in the next decade. These would give the climate forecasts with a given probability for specific countries for things, like crop yields and flooding risks. For the science of climate change, check out the IPCC report at
Technical and policy debates in this subject revolve around the speed and extent of climate change and their implication for natural and societal systems. Since it is now certain that all countries will need to adapt to climatic change with differing degree, the question is what mitigation measures should be adopted to reduce the effect locally and globally? Adaptation and mitigation are complementary and hence, both are essential.
All these issues are important from a development viewpoint but others are also important, particularly for less developed countries like ours. How will climate change interact with other factors driving change in society? How will it interact with social and economic vulnerability? Are there economical and smart ways of reducing adverse effects?
Sticky challenges affect the equity issue of climate change, particularly between developing and developed nations due to their unequal emissions of greenhouse gases, constraints on future emission and unequal exposure and capacity to adapt to the effects of major changes that are feared. All such issues require serious study and discussion in this region.
Islamabad is replete with workshops on a range of subject and occasionally, there’s one on climate change. A section of a recent meeting (25-27 April 2005) about the Karakoram region was devoted to climate and the study of glaciers, which a scientist friend attended. This is how he described it to me through an email: “I was there at 0900, (although the session was to start at 0830). The Italian chairman and his Italian colleague were on the dais but nothing was happening. At about 0930, an announcement was made about a malfunctioning computer that had been fixed and the session could start. The name of the first speaker, a Pakistani, was announced. There was no response. The speaker had not turned up. [It was the] same with the second native speaker. The third speaker was from the Department of Meteorology, a young fellow, who talked on the climate in northern areas — it was mainly data collected over the past 50 years. Then came the turn of the last speaker of the session. He was a retired highway builder who told the story of the Karakoram highway. The content was potentially interesting but the presentation was not. He kept taking as if he was sitting in a roadside hotel telling tales of his personal experiences. Eventually, after an hour (the allotted time was 15 minutes) the audience started clapping continuously and so the polite Italian chairman requested the speaker to finally end his talk.
“After tea, the session was on glaciers. The program showed three Pakistani speakers, one Italian and one from Nepal. All three Pakistanis failed to appear. So the turn of the Italian came right at the beginning and after him, spoke the Nepalese. The Italian spoke on the measurements carried out on the Baltoro Glacier over the last hundred years right up to today’s state of art technology and the Nepalese on the Glacial Lake Burst Floods in the Himalayan Region. Both were an absolute treat to listen to. It was time for lunch then, so I vanished from the scene.”
This was clearly a meeting of considerable importance for climate change but here, as in most such meetings in grand hotels, there was a definite lack of seriousness. For a critical issue such as climate change, Pakistan will need to do lot better.
The relatively recent Global Change Impact Studies Centre, the brainchild of Dr Ishfaq Ahmed, former head of the Pakistan Atomic Energy Commission (PAEC), represents a useful but modest step. It will need to be supported with funds for getting more and better trained climate specialists, modelers, experimentalists and field workers (we need better data of greenhouse gas emissions nationally) in addition to fast computers. As climate change is a truly regional and global issue, it is essential that we collaborate closely with India and other SAARC countries. It is also necessary that a centre like this in Islamabad, without a permanent location at the moment, should be located in a university. It could become an independent research unit or be a part of a department of earth science and meteorology, offering a multi-disciplinary program. The students trained here, with supplementary experience in foreign centres, could become an invaluable asset for the future.
The writer, a physicist and an engineer, writes on science, education and environment
Shrinking lakes
Lakes in two large swaths of Siberia are shrinking in size and 125 of them have disappeared altogether, a US study revealed last week.
Scientists have examined satellite photographs of 190,000 square miles of Siberia, two areas stretching south between the Ural mountains and the Arctic mining town of Norilsk. They claim the disappearance of the lakes is a consequence of global warming.
While there were 10,882 lakes larger than 40 hectares (100 acres) in 1971, there were only 9,712, in 1997 — a decline of 11 per cent.
Published in the journal Science, the study concluded: “The ultimate effect of continued climate warming on high-latitude, permafrost-controlled lakes and wetlands may well be their widespread disappearance.”
It said: “Our study reveals a widespread decline in lake abundance and area, despite slight precipitation [rain and snowfall] increases.” The study also said the total surface areas of lakes in the region had dropped by six per cent, while 125 lakes of this size had disappeared completely.
The study said the way the lake disappearances were spaced out “strongly suggests that thawing of permafrost is driving the observed losses.”
It said that in northern areas where there was continuous permafrost — a thick layer of frozen soil that rarely melts during seasonal changes — the total surface area of the lakes grew by 12 per cent. But in the southern regions, the patchy permafrost cover meant that water could drain away, leading to a considerable reduction in lake area.
“These declines have outpaced lake gains in the north, leading to an overall loss to the region,” it said.
Russian scientists disagreed that the lake disappearances could be attributed to climate change. Galina Malkova, a senior research fellow of the Moscow-based Earth Cryosphere Institute and an expert on permafrost, said: “The data shows that the increase of temperature did not exceed 0.3C. This is not enough to be considered as a factor.
“The water draining is mainly explained by soil erosion processes,” she said, adding that lakes often disappeared as they aged. “Many are gradually taken over by vegetation.”
Russia ranks quite low among global polluters. Since its industrial complex began to decline with the collapse of the Soviet Union, emission levels have sunk to levels lower than the projections when it signed up in 1992 to the Kyoto treaty to limit climate change.
As it now produces less than its allocated quota of emissions under the treaty, Moscow can sell carbon credits to other treaty signatories.
Russia, the world’s number two exporter of oil, ratified the treaty last year, bringing it into legal effect and rescuing it from obsolescence after the US, the biggest polluter, refused to sign up in 2001. — Dawn/The Guardian News Service
