Factors affecting Climate
Global Climate change
-Caused by changes in earth’s energy balance
-Changes take 100s-1000s of years
- Amount of energy earth receives from the sun is not constant
- More energy=hotter on earth
- Earth used to have one major super continent called Pangaea
- Movements caused changes in ocean and wind currents
- Changes in land and water = changes in earth’s temperature
- Water absorbs more energy before warming up and water holds on to energy for longer.
Shape of Earth’s orbit
Varies between circular and oval, causes earth to be farther than sun at certain times of the year, which means a colder climate
Varies between 22.1 degrees and 24.5 degrees, causing a part of earth to be tilting towards the sun, which means a warmer climate.
- as the earth spins, the direction of the tilt changes
- Volcanoes put SO2 into the atmosphere which shades the earth and cools it down
- air and ocean currents such as El Nino
Factors affecting local climate (short Term)
- At higher latitudes, sun is not directly overhead–>the energy is spread over a large area and feels weaker.
- Sun’s energy must also travel through more atmosphere, where some of the radiation is reflected.
- at high altitudes, atmospheric pressure is lower
- air from lower altitudes rises to higher altitude, expands, and cools down. (when it falls it becomes more dense)
- as clouds are blown upward over mountains, they lose their moisture as rainfall on the windward side.
Large Bodies of Water
- water absorbs and stores more thermal energy than land
- water heats up and cools down more slowly than land
- regions near oceans/lakes tend to be cooler in summer and warmer in winter
- regions downwind of an ocean/lakes have more precipitation
Drastic Effects of Climate Change
Effects on the atmosphere
Heat waves are becoming more and more frequent. The heat and smog may cause the deaths of elderly or ill people. As a result, in cities, city pools are open longer, and some air-conditional public buildings are kept open all night as cooling centres.
In Australia, during 2008-2009, 200 people died of excess heat (15-20 degrees more than usual).This excess heat also effects ice and and permafrost in northern Canada, which makes lifestyle in those areas impossible.
Droughts are very severe when they affect deserts, because they kill many animals and vegetation in the area. Droughts in places with alot of vegetation cause inadequate food for the nearby people and animals, which causes the climate and biome of that region to change as well.
these occur when the weather is hot and dry for a long time, the trees may become so dry that they lose their leaves, which increases the probability for wildfires. These catastrophes usually occur in the summer.
Storms such as Hurricane Sandy and other mega-storms, are linked directly to climate change, experts suggest. This means that rainfall increases and many homes get destroyed because of humans’ wrong doings. The likeliness of storms is predicted to increase by 40% by the end of the century.
Effects on Hydrosphere
As the average global temperature increases, Earth’s ice is melting. Melting ice can affect earth by:
- flooding land that is currently just above sea level
- changing habitats of shoreline plants, animals, and micro-organisms
- causing the loss of property
- changing geographic coastlines and shapes of continental coasts
- reducing the amount of fresh water available to communities
in the arctic, the amount of sea ice in the summer has decreased drastically. In the 1800s, explorers could not find the northwest sea passage because it was blocked with heavy and high walls of ice, even in the summer. Now, in the winter, it is easy to sail between Canada’s northern islands, proving that the ice has melted substantially.
Since water warms up more slowly, effects of climate change on water has not been so obvious. warming oceans are a threat to earth’s biomes because:
- As the water warms, it expands, so warmer oceans means higher sea levels, causing loss of coastal land
- warmer water absorbs less carbon dioxide, so it is less effective as a carbon sink.
- warmer water is not as ideal a habitat for plankton growth. Phytoplankton undergo photosynthesis and therefore are an important carbon sink. Warmer oceans mean less phytoplankton, less carbon dioxide absorbed, and therefore an increase in greenhouse gas emissions.
- warmer water produced more intense hurricanes, which damage land and harm people. hurricanes are also beneficial in that they transfer heat from the warm tropical oceans to colder climates.
Warming climates of certain regions causes some animals to become endangered, because their is a loss of their native climate. According to the IPCC, between 40 to 70% of all species on the planet will be extinct if the global temperature rises by 3.3 degrees Celsius. Already, 35% of all frog species are at risk. However, climate change can also cause many species to flourish, like insects, such as mosquitoes, that thrive in damp and hot climates. This will cause an increase in malaria disease. All in all, climate change disrupts and dis-balances the earth’s ecological state. Some magnificent oceanic structures such as the coral reefs are beginning to disappear due to warmer water, sedimentation, and storm damage.