Weather and Hydrology Part 1 PDF

 defined as the state of the atmosphere at some place and time, usually expressed in terms of temperature, air pressure, humidity, wind speed and direction, precipitation, and cloudiness. state of the atmosphere at a particular place during a short period of time Meteorologists study wea...

 defined as the state of the atmosphere at some place and time, usually expressed in terms of temperature, air pressure, humidity, wind speed and direction, precipitation, and cloudiness. state of the atmosphere at a particular place during a short period of time Meteorologists study weather. defined as a set of weather conditions typical of a given region together with the frequency of these conditions and their seasonal variations (Monin, 1986) denotes mean weather and the statistical weather distribution of a certain area as determined over a certain number of years (usually 30 years) Earth’s Climate System Earth’s Sphere Lithosphere – solid earth Hydrosphere – all water Atmosphere – gases (the air) Biosphere – all life ib.bioninja.com.au  Biosphere the part of earth that supports life (biota = animals, plants and microorganisms) includes water, rock and soil of the earth’s crust, and the atmosphere energy is received from the sun and the interior of the earth and is used and given off as materials are recycled prestigepuzzles.com  Lithosphere rocky material of the earth’s outer shell from the surface to about 100 km deep Crust: made of loose soil and rocks. Mantle: made of dense rock made up of nickel and iron in the form of silicate rocks its lower part is semi-solid (partially molten) rocks outer core: made up of liquid (purely molten) rock materials. inner core: center of the earth which is purely made of very hot and liquid iron and worldatlas.com nickel.  Hydrosphere body of liquid on or near the surface of the earth includes the total amount of water that can be found on the whole planet, from that on the surface - like in lakes, oceans, rivers etc. as well as water underground, and in the air (World Atlas) Because it includes all water, this also means that it encompasses water that is found in liquid, vapor, or solid (i.e ice) form. (World Atlas)  Atmosphere gaseous blanket where important gases circulate an envelop of gases surrounding the earth and bound to it permanently by gravitational force composed of clean dry air, water vapor and impurities worldatlas.com  Atmosphere within 97 km of the Earth’s surface Troposphere (0-10 km altitude) Stratosphere (10-45 km altitude) Mesosphere (45-80 km altitude), Thermosphere (80-300 km altitude). worldatlas.com worldatlas.com Earth’s Atmospheric Gases due to air circulation patterns, temperature gradients, land use practices and industrial emissions CONSTANT COMPONENTS: Proportions remain the same over time and location. VARIABLE COMPONENTS: Amounts vary over time and location. Roles of Atmosphere affects the earth’s energy balance integral component of hydrologic cycle, carbon cycle, and nitrogen cycle provides favorable climate to meet food and energy demands  GREENHOUSE EFFECT is the natural warming of the earth that results when gases in the atmosphere trap heat from the sun that would otherwise escape into space. water vapor most abundant GHG in the atmosphere largest contributor to greenhouse effect (60%) warming is caused by increasing water vapor in atmosphere due to increased evaporation act as feedback to climate (i.e. water vapor in atmosphere increases as climate warms) does not long last in the atmosphere and is removed as precipitation and condensation Factors Affecting Climate physicalgeography.net  rate at which the radiant energy from the sun is received on a surface at the top of the atmosphere perpendicular to the sun’s rays when the earth is at an average distance from the sun average solar constant is 1368 W/m2 at an average earth-sun distance of 1.496x1011 m Actual values varies by about ± 3.5% between January (Perihelion) and July (Aphelion)  Milankovitch Theory: relates climate variations to changing parameters of Earth’s orbit around the sun orbital configuration affects SR received by earth in different ways: a. changes in eccentricity b. changes in obliquity c. changes in orbital precession EARTH-SUN GEOMETRY  from elliptical to circular orbit in a pseudo-cyclic way (110,000-year cycle) larger E value causes smaller annual incident radiation  tilt of earth’s axis (current value of 23.5°) tilt varies from 21.5° to 24.5° for a period of 40,000 years causes SR intensity and sunshine duration to vary at different latitudes and time of year  earth’s axis wobbles like a spinning top due to gravitational interaction with other planets, primarily Jupiter causes progressive change in time of equinoxes for a period of 23,000 years affects temporal and spatial distribution of insolation