Atmosphere and Climate Change Chapter 13 Atmosphere and Climate Change

Factors That Determine Climate Weather and Climate are different things. Weather is the conditions in a given area at a specific time. Climate is the overall prevailing conditions of an area. Five Major Factors That Determine Climate Latitude Global Air Circulation Patterns Oceanic Current Patterns Topography Mother Nature

Latitude Distance from the equator. Makes a difference because the sun’s energy is more intense the closer to the equator. Oblique Rays Vertical Rays Oblique Rays

Atmospheric Circulation Heat radiating from Earth warms air and begins it circulating. Movement of air in cells transfers heat (and water). Rotation of the Earth causes trade winds, easterlies, and westerlies.

Oceanic Circulation Patterns Water is in motion by Earth’s rotation and winds (and warmed by the sun making it the primary source of water that falls as precipitation. Water currents help redistribute heat and keep Earth warm. Oceanic circulation makes coastal climates milder. Belfast, Ireland Moscow, Russia

Oceanic Circulation Patterns Changing Surface Patterns Southern Oscillation is the movement of masses of warm and cold water in the southern Pacific Ocean. El Nino Is characterized by a warm phase (El Nino) and a cold phase ( La Nina). Phases cause changes in climate of some equatorial regions. La Nina

Oceanic Circulation Patterns Changing Surface Patterns Pacific Decadal Oscillation is the movement of masses of cold and warm water in the northern regions of the Pacific Ocean. Is a long term oscillation lasting 20-30 years. Influences the climate of North America and the Northern Pacific.

Topography Elevation is the height above sea level. Temperature drops 110 F for every 1000 meters. Rainshadow Effect occurs as mountains cause atmosphere to drop moisture. These winds cause fires.

Mother Nature/Natural Occurances Seasonal Changes Caused by Earth’s tilt and rotation around the sun.

Mother Nature/Natural Occurances Solar Fluctations Solar energy fluctuates over an 11 year cycle from lowest amount of radiation emitted to solar maximum (the greatest amount emitted). Increased radiation in turn produces more ozone, creating a warmer atmosphere and Earth.

Mother Nature/Natural Occurances Volcanic Eruptions Primary pollutants can react with oxygen to produce haze that can reflect sunlight and cause a decrease in global temperature. Dust clouds can block sun- light.

The Ozone Layer Located in the Stratosphere, the Ozone Layer absorbs UV light from the sun’s radiation. Is being destroyed by human use of CFCs (Chloroflouro-carbons). One CFC molecule can destroy 100,000 ozone molecules.

Ozone Depletion Antarctica 1987 & 1992 – Montreal Protocol was signed. It is an international treaty to reduce CFC emissions. Still could be disrupted because it takes CFCs 10-20 years to reach ozone layer.

The Greenhouse Effect Greenhouse gases [including CFCs, Water Vapor, Methane, Nitrous Oxide, Carbon Dioxide (CO2)] trap heat. The burning of fossil fuels is a major contributor to the rise of CO2 levels in the atmosphere. Earth absorbs the energy and radiates it out as heat.

The Greenhouse Effect CO2 levels are naturally higher in winter than summer. Problem is, summer lows are not as low, and winter highs are higher and higher every year. 6CO2 + 6H2O C6H12O6 + 6O2 Since 1958 CO2 levels have increased by 17% from 314 parts per million to 368 parts per million.

Consequences of A Warmer Earth Rising Sea Levels due to melting ice caps and glaciers. Shifting Weather Patterns could cause regions that are farmland now to experience very different conditions like droughts or floods. Human Health Problems including more heat related deaths and also an increase in tropical diseases such as malaria. Agriculture could suffer because of decreased water for irrigation due to depletion of surface and groundwater. Plants/Animals could suffer (as plant species die out or decrease, every step of the energy pyramid is affected).

What Is Being Done? Kyoto Protocol is a treaty ratified by many developed countries in an effort to lower global emissions of CO2. (US did not sign) Problem is that developing countries are now starting to produce more CO2 and will continue to increase in emissions.

The End