Más contenido relacionado


thecausesofclimatechange-141020085111-conversion-gate02 (2).pptx

  1. Effects of Climate Change of natural resources Sanya Imran
  2. Climate change 1. It is a change which is attributed directly or indirectly to human activity 2. that alters the composition of the global atmosphere and which is in addition to 3. natural climate variability observed over comparative time periods”
  3. Human Causes of Climate Change • Due to an increase in population this means we need to graze more food as the demand rises. Methane is released by cows although it is a very minor gas it is very effective in retaining the heat. Since 1950, annual emissions have increased 4 times faster than the increase in C02 • In places like China were an average of 3 coal fire power stations are built, to meet demands of the economy, carbon dioxide is released when burning fossil fuels e.g. coal and oil. Fossil fuels have increased atmospheric C02 by 25% • Deforestation is caused by the need to grow more food and to build houses. This means more carbon dioxide in the atmosphere as trees generally take in the carbon dioxide hence contributing to climate change.
  4. The Enhanced Greenhouse Effect Is the increase in the natural greenhouse effect, said to be caused by human activities which increase the quantity of greenhouse gases in the atmosphere. Examples include: • Increasing car ownership • Domestic use
  5. Carbon Dioxide - Power Plants (40% of carbon emissions) - Cars (33% of carbon emissions) - Airplanes (causes an estimated 3.5% of global warming) - Buildings (12% of carbon emissions) - Deforestation (responsible for 20-25% of carbon emissions)
  6. Natural Causes – Changes of Solar Output • Solar energy also known as ‘sun spots’ works in cycles, so that the sun’s energy varies over short periods. This can increase temperature when there are more sun spots. • These cycle last for 11 years • The darker the spots, the more active and solar output energy is released. • Cooler periods, such as the Little Ice Age, and warmer periods, such as the Medieval Warm Period, may have been caused by changes in sunspot activity.
  7. Volcanic Eruption • In 1991, Mount Pinatubo in the Philippines erupted, releasing 17 million tonnes of sulphur dioxide. This was enough to reduce global sunlight by 10%, cooling the planet by 0.5°C for about a year. • 1815 eruption of Tambora in Indonesia. This was the biggest eruption in human history. In 1816, temperatures around the world were so cold that it was called ‘the year without a summer’, and up to 200 000 people died in Europe as harvests failed. The effects lasted for four to five years. Sunlight reaching earth was reduced by 10%.
  8. Variation in The Earth’s Orbit • According to one theory the Malankovitch cycles, the Earth’s orbit varies with changes to the Earth axis every 41 000 years. Theses variation are thought to be the main cause of affecting the glaciation cycle.
  9. Climate change can be assessed across short, medium and long timescales. Short-term (recent) climate change is on a timescale of decades, e.g. global warming. The medium-term (historical) timescale covers changes over the last few thousand years. Long-term climate change has occurred on geological timescales, over hundreds of thousands to millions of years.
  10. Summary • Globally 87% of energy supplied by fossil fuels • 79% of people believe the UK should reduce its use of fossil fuels • Malancvotich discovered that the Earth’s axis has a relation between the sun according to the earths tilt this affects solar radiation. • Human activities like burning fossil fuels have threatened species of natural habitats, through heating of the atmosphere has caused polar environments to melt, making it hard for polar bears to survive in changing climate condition. • There is a distinction between the weather and climate. Weather is the short term reference to atmospheric conditions. • Fossil fuels are used in transport, domestic homes and come from 48% of cars • We are dependent on our greenhouse without it the Earth would be 30 degrees colder • Surface albedo affects climate • UK has deforested from 90% to 17% • Sustainability vs cost need to think about adaptation, mitigation or suffer as a consequence. • Carbon dioxide is likely to remain in our atmosphere for decades • Indirect impacts of high temperature puts stress on cattle’s because of the infertile land • Disease patterns like malaria to increase as a result of warm temperature • Some C02 is absorbed by the oceans this affect marine organism