Preparation for Class Test 4

CHAPTER 3 VARIABLE WEATHER CHANGING CLIMATE(DIFF BETWEEN WEATHER & CLIMATE)+(HOW LATITUDE AND ALTITUDE AFFECT TEMP) WEATHER : 1) SHORT TERM,CHANGES HOURLY/REFERS TO THE SPECIFIC CONDITION OF ATMOSPHERE AT A CERTAIN TIMING(TIME FRAME). 2) IT IS OVER A VERY SMALL SCALE. FOR EXP,IT MAY BE HOT AND SUNNY IN NORTHERN PART OF SG BUT RAINING IN THE EASTERN PART OF SG(SCALE) CLIMATE : 1) LONG TERM,CHANGES MORE THAN 30 YEARS/IS AN AVERAGE CONDITION MORE THAN 30 YEARS(TIME FRAME) 2)IT IS OVER A VERY LARGE SCALE.FOR EXP,PLACES BETWEEN TROPIC OF CANCER AND TROPIC OF CAPRICORN EXPERIENCE TROPICAL CLIMATE/SIMILAR CLIMATE(SCALE) WHAT IS TEMPERATURE? -DEGREE OF HOTNESS AND COLDNESS OF THE AIR-USE DIGITAL THERMOMETER,SIX'S THERMOMETER ETC.UNIT:DEGREE CELSIUS WHY DIFFERENT PLACE EXPERIENCE DIFFERENT TEMPERATURE? ...BECAUSE OF LATITUDE AND ALTITUDE(AND TWO OTHER FACTORS)! #1.LATITUDE THE EARTH TILTS AT 23.5 DEGREE CELSIUS ON ITS OWN AXIS.HENCE,THE SUN RAYS STRIKE THE EARTH'S SURFACE AT DIFFERENT ANGLE(ANGLE OF INCIDENCE..NO MORE PHYSICS,PLS).WHEN THE ANGLE OF INCIDENCE IS BIGGER,THE SUN RAYS ARE MORE CONCENTRATED ON A SMALL AREA.THEREFORE,THE TEMPERATURE IS HIGHER AT THESE PLACES.WHERES...WHEN THE ANGLE OF INCIDENCE IS SMALLER,THE SUN RAYS SPREAD OUT OVER A WIDER AREA.HENCE,THE TEMPERATURE IS LOWER AT THESE PLACES.FOR EXAMPLE...NORTH POLE,WHICH IS AT HIGHER LATITUDE,HAVE TEMPERATURES BETWEEN -40 DEGREE CELSIUS TO 10 DEGREE CELSIUS(NO WONDER POLAR ICECAPS MELT LAH).SINGAPORE,WHICH IS AT LOWER LATITUDE,HAVE TEMPERATURES BETWEEN 23 DEGREE CELSIUS TO 34 DEGREE CELSIUS. #2.ALTITUDE -IS THE HEIGHT OF A PLACE IN RELATION TO SEA LEVEL.-NORMAL LAPSE RATE:EVERY 1KM INCREASE IN ALTITUDE,TEMPERATURE DECREASE BY 6.5 DEGREE CELSIUS.FOR EXAMPLE,SINGAPORE IS 15 M ABOVE SEA LEVEL WHILE GENTING HIGHLANDS IS 1740 ABOVE SEA LEVEL.TEMPERATURE DECEASES WITH ALTITUDE BECAUSE THE ATMOSPHERE IS MOSTLY HEATED UP BY EARTH SURFACE.THE SUN'S SOLAR ENERGY ENTERS THE ATMOSPHERE AND REACHES THE EARTH'S SURFACE IN THE FORM OF SHORTWAVE RADIATION.ABOUT 45 % OF SHORTWAVE RADIATION IS DIRECTLY ABSORBED BY THE EARTH'S SURFACE,HEATING IT UP.THE WARM SURFACE THEN EMITS HEAT IN THE FORM OF LONGWAVE RADIATION.THEREFORE,THE HIGHER THE ATMOSPHERE,THE FURTHER IT IS HEATED FROM THE SURFACE,THUS LOWER TEMPERATURES.LONGWAVE RADIATION IS ALSO ABSORBED BY GREENHOUSE GASES SUCH AS CARBON DIOXIDE.MORE LONGWAVE RADIATION IS TRAPPED NEARER THE SURFACE THAN AT HIGHER ALTITUDES.THUS,THE TEMPERATURE IS HIGHER NEARER TO THE EARTH'S SURFACE THAN AT HIGHER ALTITUDES.AIR IS LESS DENSE AT HIGHER ALTITUDE THAN LOWER ALTITUDE.DENSER AIR IS ABLE TO ABSORB MORE HEAT FROM LONGWAVE RADIATION THAN THE LESS DENSE AIR AT HIGHER LATITUDES.HENCE,IT WILL BE COOLER AT HIGHER ALTITUDES. CHAPTER TWO PLATE TECTONIC (RISKS AND BENEFITS OF LIVING IN VOLCANIC AREAS) RISKS OF LIVING NEAR VOLCANIC AREA:THEY ARE...#1.DESTRUCTION BY VOLCANIC MATERIALS#2.LANDSLIDES#3.POLLUTION#4.EFFECTS ON WEATHERWITHOUT FURTHER ADO,LETS BEGIN THE FIRST FACTOR!#1.DESTRUCTION BY VOLCANIC MATERIALS VOLCANIC MATERIALS CAN LEAD TO WIDESPREAD DAMAGE OF PROPERTIES...LAV,ESPECIALLY LOW SILICA LAVA, PYROCLASTIC FLOW(WITH HOT ROCK FRAGMENTS AT MORE THAN 80 KM/H ), INHAILING HOT ASHES AND GASES WHICH RESULT IN DEATHS.LASTLY,VOLCANIC BOMBS OF HEATED ROCKS WHICH MAY BE AS BIG AS A CAR(HUH?!),DAMAGES LIVES AND PROPERTIES(OH NO!) FOR EXAMPLE: THE ONGOING ERUPTIONS OF KILAUEA IN HAWAII SINCE 1983 HAS DESTROYED MANY HOMES AND HIGHWAYS. HMM... WHY LOW SILICA LAVA? THIS IS BECAUSE... LOW SILICA LAVA MOVES RAPIDLY AND FLOWS OVER LONG DISTANCES,CAUSING DAMAGE TO LARGER AREAS THAN THE HIGH SILICA LAVA. #2.LANDSLIDES IT CAN OCCUR DUE TO THE STRUCTURAL COLLAPSE OF A VOLCANIC CONE.THIS OBSTRUCT THE FLOW OF RIVERS WHICH CAUSES FLOOD,BLOCK ROADS AND BURY VILLAGES AND FARMLANDS. LAHARS(MIX OF PYROCLASTS AND GLACIER ICE)IS ABLE TO ENGULF AN ENTIRE TOWN. FOR EXAMPLE: ERUPTIONS OF NEVADO DEL RUIZ IN THE ANDES MOUNTAINS OF SOUTH AMERICA IN 1985 RELEASED A PYROCLASTIC FLOW. #3.POLLUTION ASH PARTICLES MAY BLOCK SUNLIGHT,SUFFOCATE CROPS AND CAUSE SEVERE RESPIRATORY PROBLEMS FOR PEOPLE & ANIMALS.RELEASE OF GASES SUCH AS HYDROGEN,CARBON MONOXIDE,SULPHUR DIOXIDE,MAY BE HARMFUL TO PEOPLE. FOR EXAMPLE: 2010 ERUPTIONS OF EYJAFJALLAJOKULL(???) IN ICELAND.-FINE ASH THAT CAN BE CARRIED BY WINDS EASILY OVER THOUSANDS OF KM AND IMPACT AREAS FURTHER AWAY.-REDUCED VISIBILTY-AFFECTED FLIGHTS IN EUROPE 2010 DUE TO VOLCANIC ASH CLOUDS CONTAINING TINY PARTICLES OF ABRASIVE SAND,GLASS AND ROCK.-ECONOMIC DAMAGE TO AIRLINE INDUSTRY UP TO US $1.8 BILLION(WOW)