Climate Changes Lecture Notes PDF

Climate changes (lecture no. 4) Speaker Prof. Adel Kamel Review to prepare ourselves for midterm, we have to read these points very well since midterm exam will be from these point and I explained them in the previous lectures - Climate change is a change in the average temperatur...

Climate changes (lecture no. 4) Speaker Prof. Adel Kamel Review to prepare ourselves for midterm, we have to read these points very well since midterm exam will be from these point and I explained them in the previous lectures - Climate change is a change in the average temperature and cycles of weather over a long period of time. - With climate change, the planet is becoming warmer. - Rising temperatures are causing sea levels to increase. - The rising water can cover coastal areas, destroying habitats and displacing whole populations from low-lying areas. - The increase in global temperatures is causing a reduction in sea ice. - The bright surface of the ice reflects 80% of the sunlight that hits it back into space. - The global temperature is set to continue rising as a result of greenhouse gases that are already in the atmosphere. The problems that we are already experiencing - Carbon dioxide (CO2), methane (CH4) and water vapour (H2O) are among greenhouse gases that are found in the atmosphere. - The greenhouse gas molecules absorb some of the energy, trapping it in the atmosphere. - The rapid climate change we are experiencing now is due to three main human activities: Burning fossil, Deforestation, and Reduction of biodiversity. - The USA, the EU and China alone have contributed around 60% in the climate changes. The countries who have contributed the least to the climate crisis are the ones who are affected the most. The increasingly warmer than average temperature of the Planet over Bushfire Aftermath On Kangaroo Island by © Brad Fleet / Newspix licensed under CC BY  Continue reviewing - The bouncing of Earths heat energy off the greenhouse gases in the atmosphere back towards the Earth’s surface is called the GREENHOUSE EFFECT - We measure recent temperature changes directly with thermometers - We measure long term temperature changes indirectly through: ◼ Ice cores ◼ Coral remains ◼ Tree rings ◼ Historical records We observe the effects of warmer temperatures: ❑ Melting of glaciers - We observe the effects of warmer temperatures: ❑ Increase in ocean water levels - The VAST MAJORITY* of scientists believe that global warming is due to an increase in greenhouse gas emissions from human activity. - A very small minority think that global warming might be due to natural fluctuations of Earth’s temperature.  Continue Reviewing - Even a 1°C increase in global temperature will lead to: ◼ Melting glaciers ◼ Drowning of islands ◼ Coastal flooding ◼ Change in weather patterns ◼ Increase in fierce storms ◼ Difficulty growing food due to floods/droughts/salt water infiltrating fresh water supplies ◼ Diseases emerging in different regions of the globe. ◼ Increase in weather related mortality. - Alternatives to Burning Fossil Fuels Renewable Energy Sources - Earth’s 4 Interrelated Physical Systems are Lithosphere, Biosphere, Hydrosphere, and Atmosphere - The atmosphere traps energy from the sun and keeps the Earth’s surface warm enough for water to exist as a liquid. - Atmosphere is Comprised of a mixture of invisible permanent and variable gases as well as suspended microscopic particles (both liquid  Continue Reviewing - Nitrogen N2 represents 78 % of the atmosphere, Oxygen, Argon,…. - Weather refers to the conditions in the atmosphere at a given place and time OR the day-to-day or short-term change in atmospheric conditions. - Climate is the average weather condition that occurs at a place over a period of time, usually two or three decades - TROPOSPHERE Temperature decreases as altitude increases. - STRATOSPHERE Temperature increases as altitude increases MESOSPHERE Temperature decreases as altitude increases - Estimated temperature without greenhouse gases -5 - Actual average temperature 15 Untitled by © Shutterstock / Ritesh Chaudhary / WWF licensed under CC BY Thank you