Using appropriate technology for sustainable development
and for the relief of poverty in developing countries
SF Environmental Trust, 9, The Pastures, York, YO24 2JE, UK
Human Activity -> Increased Greenhouse gases -> Global Warming -> Climate Change
Climate change due to human activity is the greatest threat to our survival. The
evidence for this is overwhelming. It is not the purpose of this small leaflet to
set out to prove the link between human activity, carbon emissions, global warming
and climate change. What we do point out is the possible effects of climate change
and what we can do to minimise our impact on the environment.
Effects of Global Warming
It is hard to accurately predict the exact effects of global warming. However it
is possible to highlight trends.
1 degree of warming
Temperatures have risen by 0.74 degrees C in the last 100 years.
Low-lying atoll countries such as the Maldives will be preparing for extinction as
sea levels rise, and mainland coasts – in particular the eastern US and Gulf of Mexico,
the Caribbean and Pacific islands and the Bay of Bengal – will be hit by stronger
and stronger hurricanes as the water warms. The western United States once again
could suffer perennial droughts, far worse than the 1930s. Deserts will reappear
particularly in Nebraska, but also in eastern Montana, Wyoming and Arizona, northern
Texas and Oklahoma. As dust and sandstorms turn day into night across thousands of
miles of former prairie, farmsteads, roads and even entire towns will be engulfed
With current levels of carbon emissions, a 1 degree rise in the Earth’s temperature
cannot be avoided.
1 to 2 degrees of warming
Temperature rises of between 1 and 2 degrees C is expected by 2050. The hot European
summer of 2003 will become the norm. The heat wave in 2003 was the hottest since
1540 and resulted in the death of an estimated 30,000 people. Farmers lost £8 billion
worth of crops, and Portugal alone suffered £8 billion of forest-fire damage. The
flows of the River Po in Italy, Rhine in Germany and Loire in France all shrank to
historic lows and there was not enough water for irrigation and hydroelectricity.
In the two-degree world, nobody will think of taking Mediterranean holidays. The
movement of people from northern Europe to the Mediterranean is likely to reverse,
switching eventually into a mass scramble as Saharan heat waves sweep across the
Med. People everywhere will think twice about moving to the coast. When temperatures
were last between 1 and 2C higher than they are now, 125,000 years ago, sea levels
were five or six metres higher too. By the time global temperatures reach two degrees
of warming in 2050, more than a third of all living species could face extinction.
There is a 93% chance of avoiding 2 degrees of warming, but only if emissions of
greenhouse gases are reduced by 60% over the next 10 years.
2 to 3 degrees of warming
This level of warming will be apocalyptic to the Earth and all the species living
on it. Sea levels could rise by 25 metres and food and water shortages will turn
much of the world’s population into refugees.
Warmer seas absorb less carbon dioxide, leaving more to accumulate in the atmosphere
and intensify global warming. Huge amounts of carbon are stored in the soil, the
half-rotted remains of dead vegetation. As soil warms, bacteria accelerate the breakdown
of this stored carbon, releasing it into the atmosphere.
Chance of avoiding three degrees of global warming is poor if the rise reaches two
degrees and triggers carbon emissions from soil, plants and seas.