Climate Climate

Introduction Introduction Climate is a generalized pattern for weather over a period of time Climate is a generalized pattern for weather over a period of time Weather describes the changes that occur to the atmospheric conditions over short periods of time. Weather describes the changes that occur to the atmospheric conditions over short periods of time.

Major Climate Groups Major Climate Groups Factors Determining Climate Factors Determining Climate Temperature Temperature Moisture Moisture Movement of Air Movement of Air

Low Latitudes Low Latitudes Have vertical solar radiation at noon some times of the year Have vertical solar radiation at noon some times of the year High Latitudes High Latitudes Have no vertical solar radiation at noon some times of the year. Have no vertical solar radiation at noon some times of the year. Middle Latitudes Middle Latitudes Between high and low latitudes. Between high and low latitudes.

Latitude groups based on incoming solar radiation. The low latitudes receive vertical solar radiation at noon some time of the year, the high latitudes receive no solar radiation at noon during some time of the year, and the middle latitudes are in between. Latitude groups based on incoming solar radiation. The low latitudes receive vertical solar radiation at noon some time of the year, the high latitudes receive no solar radiation at noon during some time of the year, and the middle latitudes are in between.

Tropical Climate Zone Tropical Climate Zone Near the equator and receives the greatest angle of sunlight throughout the year. Near the equator and receives the greatest angle of sunlight throughout the year. Polar Climate Zone Polar Climate Zone The Sun never sets during the summer and never rises during the winter. The Sun never sets during the summer and never rises during the winter. Temperate Climate Zone Temperate Climate Zone Average temperatures that are between the two extremes Average temperatures that are between the two extremes

Regional Climate Influence Regional Climate Influence Altitude Altitude Higher altitudes radiate more energy back into space. Higher altitudes radiate more energy back into space. Temperature decreases with altitude Temperature decreases with altitude Mountains Mountains Decreasing temperature with altitude Decreasing temperature with altitude Uplifting effect on air masses Uplifting effect on air masses

Large Bodies of Water Large Bodies of Water high specific heat and loses energy by evaporation. high specific heat and loses energy by evaporation. This has the effect of keeping the temperatures more constant from night to day on a land mass near a large body of water This has the effect of keeping the temperatures more constant from night to day on a land mass near a large body of water Ocean Currents Ocean Currents Currents move large amounts of water from different parts of the world. Currents move large amounts of water from different parts of the world. Can warm or cool land depending upon the origin of the current Can warm or cool land depending upon the origin of the current

Ocean currents can move large quantities of warm or cool water to influence the air temperature of nearby landmasses. Ocean currents can move large quantities of warm or cool water to influence the air temperature of nearby landmasses.

10 In science, climate is determined by the use of a P/Ep ratio. P = the amount of precipitation an area receives over the year Ep = the amount of liquid water that evaporates/transpires into water vapor throughout the year. Ratio of 1.2 or higher = Humid Climate Ratio of 0.8 to 1.2 = Sub-humid Climate Ratio of 0.4 to 0.8 = Semi-arid Climate Ratio of 0.4 or less = Arid Climate The top number goes into the calculator first!!!

11 Climate Change Climate Cooling – Ice ages have occurred Four major continental glaciations are recorded in North America. These periods can be caused by: 1.Decrease in the Sun’s energy output, indirectly related to Sunspots. 2.Change is the Earth’s orbital period. 3.Change in the inclination (tilt) of the Earth’s axis (Procession). 4.Volcanic eruptions release ash that blocks the Sun’s rays. 5.Asteroid/Meteor impacts shoot dirt into the atmosphere that block the Sun’s rays. 6.Plate Tectonics move the continents around the Earth. Each location will have a different climate. 7.During an ice age, more light gets reflected back into space and keeps the atmosphere from heating up again.

12 Climate Warming – rock layers show that this does happen. These periods can be caused by: 1.Increase in the amount of greenhouse gasses (carbon dioxide, and water vapor) added to the atmosphere. This holds in more infrared (heat) that the Earth tries to release at night. 2.Destruction of rain forests stops the process of plants/trees removing the carbon dioxide from the air and releasing oxygen back into the air. 3.Changes in the Earth’s orbit. 4.Change in the inclination (tilt) of the Earth’s axis. 5.Increase in the Sun’s energy output. 6.Volcanic eruptions can release a lot of carbon dioxide into the atmosphere which will trap the heat b/c it is a greenhouse gas. 7.Plate tectonics will move the continents into different locations. 8.Urbanization

13 El Nino La Niña is characterized by unusually cold ocean temperatures in the Equatorial Pacific, compared to El Niño, which is characterized by unusually warm ocean temperatures in the Equatorial Pacific.El Niño Every three to five years, driven by a reversal in the trade winds, an El Nino, a huge bulge of warm water under a blanket of tropical storms, hits the west coast of USA and South America., burying the cool Humboldt Current and dropping heavy rains and a great deal of bad weather on the west coasts of Peru and Ecuador, and Calfiornia, often around Christmas--hence the name El Nino (the boy), in honor of the Christ Child.

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Humid Humid Moist Moist More than 50 cm (20 in) of rain per year More than 50 cm (20 in) of rain per year Semiarid Semiarid Between arid and humid Between arid and humid 25 – 50 cm (10 – 20 in) of rain per year 25 – 50 cm (10 – 20 in) of rain per year

Local Climates Local Climates Microclimates Microclimates A local pattern of climate influenced greatly by the local conditions. A local pattern of climate influenced greatly by the local conditions.

This map highlights the approximate location of the major types of climates in North America. This map highlights the approximate location of the major types of climates in North America.