Physical Effects of Climate Change

Effects of Climate Change in the Atmosphere  Heat Waves  Drought  Wildfires  Storms  Floods

Heat Waves  Extreme Heat Alerts often involve hot humid smoggy air  These result in increased use of air conditioning and in wildfires, both actions that increase greenhouse gases  Warm air warms the surface of the planet, leading to thawing of ice and previously permanently frozen soil (permafrost)

Drought  Most severe near deserts  Seasonal rains have stopped  People are unable to grow food – increased famine Ex. Ethiopia

Wildfires  When weather is hot and dry for a long time trees become dry and lose their leaves  Probability of wildfires increase  Frequency of wildfires is increasing globally

Storms  The rapid increase in global temperature has caused changes in the frequency and severity of storms

Floods  When air temperatures rise rapidly in the spring,snow can melt too quickly for rivers and streams to handle  These seasonal floods are becoming more frequent

Effects of Climate Change in the Hydrosphere  Melting Ice  Ocean Warming  Ocean Currents

Melting Ice 1  As the average global temperature increases, the Earth’s ice (sea and glacier) is melting  The average level of the world’s oceans has increased by about 20 cm in the last 100 years

Melting Ice 2 Melting ice can affect the Earth by:  Flooding land that is currently just above sea level  Changing habitats of shoreline plants, animals and micro- organisms  Causing loss of property  Changing geographic coastlines and shapes of continental coasts  Reducing the amount of fresh water available to communities

Melting Ice 3

Ocean Warming 1  The impact of rising temperatures on oceans is less obvious than those on land  Water warms up more slowly  The average ocean temperature has increased by approx. 0.6 ºC in the last 100 years

Ocean Warming 2  As the water warms it expands so warmer oceans mean higher sea levels  This leads to loss of coastal land

Ocean Warming 3  Warmer water absorbs less carbon dioxide so is less effective as a carbon sink

Ocean Warming  Warmer water is not ideal for phytoplankton growth  Phytoplankton photosynthesize and are an important carbon sink  Warm oceans mean fewer phytoplankton

Ocean Warming  Warmer water produces more intense hurricanes

Ocean Currents 1

Ocean Currents 2  Melting ice and warming oceans can change the flow of ocean currents  As ice melts it adds fresh water to the oceans  Fresh water is less dense than salt water  The change of salinity affects the mechanisms that drive currents  The North Atlantic deep-water current could slow down to about half its present speed

Effects of Climate Change on Wildlife  Range Shifts  Threatened Species  Benefits (?)

Range Shifts EX. In February, the Audubon Society released an analysis of data compiled over almost half a century that they say suggests that a slow, northbound shift of wintering grounds for almost every type of North American bird was directly linked to global warming.

Threatened Species  The change in climate will force many organisms to adapt, migrate or become extinct  Between 40 – 70 % of all species are at risk of extinction if the global average temperature increases by only 3.3 ºC

Organisms that benefit from Climate Change EX. A new study identifies starfish as one of the possible winners from rising ocean temperatures and carbon dioxide concentrations. Increased temperature and acidity will significantly boost the echinoderm's (Pisaster ochraceus, a species of sea star) growth rate

The End