Geography Reference
In-Depth Information
average global temperatures could rise by 5°C. Substantial impacts
from such increases are anticipated. As Sir Nicholas Stern put it in
his 2006 report for the UK government on the economic impacts
of climate change, 'Such changes would transform the physical
geography of the world. A radical change in the physical geo-
graphy of the world must have powerful implications for the
human geography - where people live, and how they live their
lives'. Indeed a 2010 report for the US National Research Council
(
Climate Stabilization Targets: Emissions, Concentrations, and Impacts
over Decades to Millennia
) suggests that the Earth is now entering a
new geological epoch called the Anthropocene during which
changes to the planet's environment will be dominated by effects
of human activities, notably emissions of carbon dioxide. Because
carbon dioxide is long lived in the atmosphere then emissions now
can lock the climate system into a range of impacts over many
generations.
Key potential impacts include:
• Theremaybemoresevereweatherevents(storms,loods,hur-
ricanes, heatwaves, droughts etc.) as a warmer Earth means there
is more energy available for atmospheric and oceanic transfers.
For example, there could be a 10 per cent increase in average
hurricane wind speed.
• Warmingmayinducesuddenshiftsinregionalweatherpatterns
such as the monsoons or the El Niño Southern Oscillation. This
could have major consequences for water availability, crops,
flooding and wildfire in tropical regions. Some climate models
predict a more frequent and intense El Niño, perhaps even
causing replacement of the rainforest of Brazil by
savanna
.
• Meltingglacierswillatirstincreaseloodriskandthenonce
depleted reduce water supplies. Large parts of the Indian sub-
continent, China and the Andes rely on summer glacial meltwa-
ter to provide water for crops and to drink. Without this regular
supply new ways will have to be found to capture water for
around 1 billion people.
• 40percentoftheworld'spopulationlivewithin100kilometres
of the coast and two-thirds of the world's largest cities are found
there. Rising sea levels from ice melt and the expansion of the
water upon warming could result in hundreds of millions of
