1.17k likes | 1.65k Views
CLIMATE AND CLIMATE CHANGE. Jill F. Hasling, President Certified Consulting Meteorologist. Weather Research Center Houston, Texas www.wxresearch.com. What is the ‘Greenhouse Effect’?
E N D
CLIMATE AND CLIMATE CHANGE Jill F. Hasling, President Certified Consulting Meteorologist Weather Research Center Houston, Texas www.wxresearch.com
What is the ‘Greenhouse Effect’? The Earth’s Greenhouse effect works by the atmosphere facilitating convection . In other words, the Earth’s ‘greenhouse effect’ works by modulating radiation. With out the ‘greenhouse effect’, the Earth would not be habitable. Without the ‘greenhouse effect’ the temperature of the earth would be -18 deg C. When you add the ‘greenhouse effect’ back in the temperature is ~33 deg C.
What is Climate? Climate is the average and variations of weather in a region over long periods of time.
What is Climate? Climate is determined by the long-term pattern of temperatures and precipitation averages and extremes at a location. Climate descriptions can refer to areas that are local, regional, or global. Climate also describes different time intervals, such as decades, years, seasons, months or specific dates of the year.
What is Climate? Climate is not the same thing as weather. Weather is the minute by minute variable conditions of the atmosphere on a local scale. Climate is a conceptual description of an area’s average weather conditions and the extend to which those conditions vary over long time intervals.
What is Climate Change? Climate change is a significant and persistent change in the area’s average climate conditions or their extremes. Climate has changed in the past, is changing now and will change in the future.
Types of Climates • A -- TROPICAL CLIMATE • B-- DRY CLIMATE • C -- MOIST SUBTROPICAL MID-LATITUDE CLIMATE • D-- MOIST CONTINENTAL MID-LATITUDE CLIMATE • E-- POLAR CLIMATE
Types of Climates • A TROPICAL CLIMATE • Climates in which the average temperature for all months is greater than 64°F (18°C). • Extend northward and southward from the equator to about 15 to 25 degrees latitude. • Example: Key West, FL
Types of Climates • BDRY CLIMATE • Arid and semi-arid deserts and steppes; evaporation exceeds precipitation. • Extends from 20 to 35 degrees latitude North and South of the Equator. • Example: Albuquerque, NM
Types of Climates • CMOIST SUBTROPCIAL MID-LATITUDE CLIMATE • Warm and humid summers (with frequent thunderstorms) and mild winters. Warmest month is above 50°F (10°C). Coldest month is above 32°F (0°C). • Extends from 30 to 50 degrees latitude mainly on the eastern and western borders of most continents. • Example: Houston, TX
Types of Climates • DMOIST CONTINENTAL MID-LATITUDE CLIMATE • Warm to cool summers and cold winters. Warmest month is above 50°F (10°C). Coldest month is below 32°F (0°C). • Extends poleward from the moist subtropical mid-latitude • climate regions. • Example: St. Paul, MN
Types of Climates • EPOLAR CLIMATE • Cold temperatures all year with the warmest month below 50°F (10°C). • Found on the northern coastal areas of North America, Europe, Asia, and on the land masses of Greenland and Antarctica. • Example: Barrow, AK
A - Tropical B - Dry C - Mid-latitude subtropical D - Mid-latitude continental H - Highlands
Factors that Influence Climate • Solar radiation received at a particular latitude
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence • Location of global high and low pressure zones
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence • Location of global high and low pressure zones • Heat exchange from ocean currents
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence • Location of global high and low pressure zones • Heat exchange from ocean currents • Distribution of mountain barriers
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence • Location of global high and low pressure zones • Heat exchange from ocean currents • Distribution of mountain barriers • Pattern of prevailing winds
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence • Location of global high and low pressure zones • Heat exchange from ocean currents • Distribution of mountain barriers • Pattern of prevailing winds • Distribution of land and sea
Factors that Influence Climate • Solar radiation received at a particular latitude • Air mass influence • Location of global high and low pressure zones • Heat exchange from ocean currents • Distribution of mountain barriers • Pattern of prevailing winds • Distribution of land and sea • Altitude
Influences to weather patterns by other natural re-occurring climate cycles • El Niño • La Niña • Drought • Monsoon
Normal Conditions • Strong easterly trade winds in the tropical Pacific push surface waters toward the west. • Waters heat up more as they move toward the western Pacific Ocean because of longer sun exposure. • Cooler waters off the coast of Peru in the eastern Pacific due to upwelling.
El Niño Conditions • Weaker easterly trade winds in the central and eastern Pacific Ocean. • This causes the normal upwelling of the cold water from below the surface to stop and the warm surface water to remain.
Affects of El Niño • Impacts to the continental US: • Temperatures in the winter are warmer than normal in the North Central States and cooler than normal in the Southeast and the Southwest. • Increase in the rainfall across the southern United States from Texas to Florida. • Increase in upper level winds over the Atlantic which could cause fewer hurricanes.
1902-1903 1905-1906 1911-1912 1914-1915 1918-1919 1923-1924 1925-1926 1930-1931 1932-1933 1939-1940 1941-1942 1951-1952 1953-1954 1957-1958 1965-1966 1969-1970 1972-1973 1976-1977 1982-1983 (Major event) 1986-1987 1991-1992 1994-1995 1997-1998 (Major event) 2002-2003 El Niño YearsTypically occur every 3 to 5 years and last about one year. • 2006-2007
La Niña Conditions • Stronger than normal easterly trade winds in the central and eastern Pacific Ocean. • This causes more upwelling off the western coast of South America resulting in cooler than normal surface water across the eastern equatorial Pacific Ocean.
Affects of La Niña • Impacts to the continental US: • Wetter than normal conditions across the Pacific Northwest. • Drier and warmer than normal conditions across much of the southern United States. • Decrease in upper level winds over the Atlantic which could increase hurricane activity.
1903-1904 1906-1907 1908-1909 1916-1917 1920-1921 1924-1925 1928-1929 1931-1932 1938-1939 1942-1943 1949-1950 1954-1955 1964-1965 1970-1971 1973-1974 1975-1976 1988-1989 1995-1996 1998-1999 2000-2001 Early 2006 Late 2007-2008 La Niña YearsTypically occur every 3 to 5 years and last about one year.
Drought A period of abnormally dry weather sufficiently prolonged for the lack of water to cause serious hydrologic imbalance in the affected area.
Drought A period of abnormally dry weather sufficiently prolonged for the lack of water to cause serious hydrologic imbalance in the affected area. Causes serious problems such as crop damage and/or water supply shortages.
Drought A period of abnormally dry weather sufficiently prolonged for the lack of water to cause serious hydrologic imbalance in the affected area. Causes serious problems such as crop damage and/or water supply shortages. Severity of drought depends upon the degree of moisture deficiency, the duration, and the size of the affected area.
Monsoon A period of seasonal winds; strongest on the southern and eastern sides of Asia.
Monsoon A period of seasonal winds; strongest on the southern and eastern sides of Asia. Monsoon climate -- Type of climate found in regions subject to monsoons and characterized by a dry winter and a wet summer.
Monsoon A period of seasonal winds; strongest on the southern and eastern sides of Asia. Monsoon climate -- Type of climate found in regions subject to monsoons and characterized by a dry winter and a wet summer. For example, India’s southwest monsoon lasts from June to September and brings vital rain for the country’s farmers, but it also causes massive destruction, floods, mudslides, collapsing houses, and lightning strikes killing hundreds of people each year.
Using Climatology to Study Specific Weather Events Tropical Cyclones Floods Droughts Winter Storms Tornadoes Rainfall Snowfall Temperatures
For Example: Tropical Cyclone Climatology in the Atlantic
Atlantic Basin Category 5 Hurricanes 31 Category 5 Hurricanes have occurred since 1900 Lowest Pressure – Hurricane Wilma 2005 - 882 mbs
Atlantic Basin Category 5 Hurricanes 31 Category 5 Hurricanes have occurred since 1900 Lowest Pressure – Hurricane Wilma 2005 - 882 mbs Highest maximum sustained winds – Hurricane Allen 1980 - 165 Knots
Atlantic Basin Category 5 Hurricanes 31 Category 5 Hurricanes have occurred since 1900 Lowest Pressure – Hurricane Wilma 2005 - 882 mbs Highest maximum sustained winds – Hurricane Allen 1980 - 165 Knots Most Category 5 Hurricanes per season 2005 – (Four) – Emily, Katrina, Rita and Wilma 1961 – (Two) – Carla and Hattie 1960 – (Two) – Donna and Ethel 2007 - (Two) - Dean and Felix
Hurricane Strikes on the United States Mainland 1851-2006 Category Strikes 5 3 4 18 3 75 2 73 1 110 TOTAL 279 Major 96 Category 3 or higher at landfall
Hurricane Strikes in Texas 1851 to 2007 Category 1 2 3 4 5 All Cat 3+ Texas 24 18 12 7 0 61 19 [North] 13 7 3 4 0 27 7 [Central] 7 5 2 2 0 16 4 [South] 7 7 7 1 0 22 8 USA 110 73 75 18 3 279 96