GLOBAL CLIMATE CHANGE
6 October 2007
Hazel Prowse

Report and notes of RAE 2007 International Lecture by Dr R K Pachauri, chairman of the IPCC (Intergovernmental Panel on Climate Change), at RIBA on 3 October — a week before he shared the Nobel Peace Prize with Al Gore.

He said the role of science was to gather knowledge of the complex relationships between humans and the environment, and to define specific solutions for large scale application. He produced the well—known graphs of both global temperature rise, and the frightening one of carbon dioxide increase.

There is no argument about global warming; arctic warming is at twice the rate of the rest of the planet and we see the reduction in the snow cover in the northern hemisphere. The temperature of the sea is also rising, but not as fast as that of the land; even if greenhouse gases were stabilised at today’s level, the seas would still be expanding, as it takes time to do so.

Is it the our fault? YES

Precipitation is also rising, with the highest rates in temperate regions, less in sub—tropics and tropics. At same time, there are more extreme events, such as floods in the UK, and longer
droughts in Australia. Athens reached 470C this year, and there is increased cyclone activity. 20—30% species are at risk of extinction if the temperature rises more than 1.5 — 2.50C, and coral reefs are among the most vulnerable sites. There will be more malnutrition in the Sahel, and countries reliant on rain—fed agriculture.

Coastal settlements at risk include the Rhine, Mississippi, Amazon, Orinoco, West Africa and India, with the outlets of the Mekong, Nile and Ganges in most danger.

Adaptation is necessary, and not just for past activity. Currently we are trying crop diversity, water management and disaster risk management, but these are limited and uneven.

Future? We expect continued emissions to result in temperature rises of +1.80 to 40C over the 21st century, and if nothing is done, the rise will be 40 However, adaptation alone cannot cope, and there will be cost rises, too. We need a mix of solutions.

If carbon dioxide in the atmosphere is stabilised at 445—490 ppm, it would peak in about 2015, and fall back to its 2000 level in 2030; the temperature rise would be 2 — 2.40.

Society must decide what to do to limit change. IPCC has looked at several changes in the generation and use of energy, and believes the potential is in fact enormous.

We could stabilise with existing technologies — (a) modern synthetics, (b) renewables, (c) advanced coal, gas and nuclear, (d) CO2 capture and sequestration, (e) combined heat & power.

Transport uses 26% of world energy — we could look at air a,id rail traffic. Then we could save 30% in buildings. We could make more of active & passive solar energy, and 4m below the surface of the earth, the temperature is uniform, giving scope for ‘free’ heat. Engineers, architects and builders should act, and we should make more efficient appliances. Bio—energy offers possibilities, but it must NOT compete with food crops!

Some countries use 80% of their water in agriculture.
Dr Pachauri said he did not want to scare us, but he was just reporting what was found at the IPCC. There IS a sense of urgency, and we do need to act...

Most questions from the audience were quasi—political but recognised the differences across the world. Engineers should look at technologies that have global application.

Not every country can afford a Thames Barrier. Carbon trading can be used to transfer capital funds into China and India; China says clean coal is fine, but if we want carbon
sequestration we must pay for it.

Nobody mentioned over—population and my question on population numbers was not called.