MAP PROJECTIONS Since we cannot carry a globe into the field, we need to figure out how to represent the curved surface on a flat piece of paper. It is impossible to represent Earth surface onto a flat surface without distortion!!!

PRINCIPAL PROJECTIONS MAP PROJECTIONS PRINCIPAL PROJECTIONS Azimuthal

CYLINDRICAL PROJECTION Areas close to the Equator present very little distortion The closer to the poles the more distortion the map presents

CILINDRICAL: Mercator projection:

PROPERTIES OF MAP PROJECTIONS CONIC PROJECTION AZIMUTHAL PROJECTION PROPERTIES OF MAP PROJECTIONS Conformal: when the direction is maintained at any point on the map. Shape is preserved locally Equal-area: all mapped areas have the same proportional relationship to the areas on the Earth

Mercator Projection (conformal) Lambers equal-area conic projection Which map should we use to analyze and compare snow regions?

GLOBAL TIME TIME ZONES OF THE WORLD 24 hours for a full rotation respect to the Sun Variation of time with longitude TIME ZONES OF THE WORLD World divided into 24 standard time zones (15° each zone) 15º longitude=1 hour

INTERNATIONAL DATE LINE The 180° meridian is used as International Date Line to set 1 day (advance or back) in the calendar If you travel westward: advance one day If travel eastward: set calendar back by a day

Global time is called Greenwich Mean Time or GMT TIME ZONES OF THE WORLD Primary standard meridian is the Greenwich Meridian (Prime Meridian, 0º longitude) Global time is called Greenwich Mean Time or GMT Examples: Tuesday 3am in Spain is ___________ in Newark,DE Saturday 10 am in California is ______ in China

THE SUN-EARTH RELATIONSHIP Why is this relationship important? Solar radiation drives nearly all of the natural processes on Earth’s surface Solar radiation drives nearly all of the climate processes (seasons, temperature, radiation, evaporation, transpiration, precipitation)

THE SUN-EARTH RELATIONSHIP EARTH REVOLUTION AROUND THE SUN July 4 January 3 Does it mean that in January we’ll have more temperature? 11

THE SUN-EARTH RELATIONSHIP THE TILT OF THE EARTH’S AXIS The Earth is tilted at an angle of 23.5° 12

SOLSTICE AND EQUINOX CONDITIONS AND SEASONS One of the poles is tilted away from the Sun EQUINOX: The Earth’s axial tilt is neither toward nor away from the Sun

SOLSTICE CONDITIONS One of the poles is tilted away from the Sun JUN 21-22 DEC 21-22 Observe the circle of illumination at different latitudes: because the tilt toward the Sun, we only have equal halves in Equator.

The Earth’s axial tilt is neither toward nor away from the Sun EQUINOX CONDITIONS The Earth’s axial tilt is neither toward nor away from the Sun MARCH 21 and SEP 22 The circle of illumination has equal halves in all latitudes

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THE SUN-EARTH RELATIONSHIP Location with 12 hours of day and 12 hours of night along all year? Location with 24 hours of night on June 21st? Location with 12 hours of day and 12 hours of night on September 23rd? Location with 24 hours of light on June 21st? Location with 24 hours of night on December 21st? 17

INSOLATION AND SUN ANGLE The angle of the Sun’s rays determines the intensity of insolation on the ground This is controlled by the latitude of the location and the time of the year.

INSOLATION AND SUN ANGLE wintertime The same amount of energy over different areas

WORLD LATITUDE ZONES EQUATORIAL: Malasya Min: 72.4 F Max: 89 F

TROPICAL: Belo Horizonte (Brazil) SUBTROPICAL: El Cairo (Egypt) Min: 61.0 F Max: 81 F Min: 62.4 F Max: 81 F SUBARTIC Copenhagen (Denmark) MIDLATITUDE: Baltimore Min: 41.0 F Max: 52.0 F Min: 45.0 F Max: 65.0 F

Rothera Point (Antartic Peninsula) Mean: 23.0 Wedell seal pup “Solar Pillar” (a visual phenomenon; the sun is reflected very strongly by ice crystals, so the reflection is almost as brightest as the sun itself) SOUTH POLAR Amundsen-Scott (90°S) American base at South Pole Mean: -57.0F Vostok (78°S): Russian base. One of if not the coldest place on Earth. Mean Temp: -67.0 F or –55.0°C