World Biomes and Climatographs History: Ancient Greeks used to classify the environment into zones which had different degrees of warmth. This resulted in Aristotle describing the terrain in terms of flora and fauna. Main characteristics and variables used to define biomes is: Precipitation Temperature Climate - 30 year records. Invention of instruments in the 17th and 18th century allowed for data and records to be used for classification of global climates The main elements of the weather that are measured are- 1. Temperature 2. Wind (Direction and Speed) 3. Humidity 4. Precipitation 5. Sunshine

World Biomes Map Our world is a diverse and beautiful place filled with a range of environments. As Earth scientists, we strive to understand the Earth as a system and how each part compares and works with another. This functionality defines the study of both the atmosphere and Earth’s surface. We know that heat transfer occurs constantly due to uneven heating of the Earth’s surface and this effects the physical and biological landforms based on the climate conditions, controlled by convective cells and solar insolation.

World Biomes and Climatographs Earth’s tropospheric convective cells are the driving force behind the surface landforms , weathering and erosion and the physical and biological processes that occur in each particular region of the planet. Air pressure systems/belts control the function and resultant environmental processes based on the simple rule of whether air rises or sinks. Evaporation, condensation, precipitation and air instability are all created by rising air in areas of low pressure. The creation of systematic and symmetrical areas of low and high pressure produce similar surface environments consistent with precipitation and the amount of sunlight annually (temperature) . 1) Latitude and its influence on solar radiation received. 2) Air mass influences. 3) Location of global high and low pressure zones. 4) Heat exchange from ocean currents. 5) Distribution of mountain barriers. 6) Pattern of prevailing winds. 7) Distribution of land and sea. 8) Altitude.

Atmospheric Circulation and Biomes In general: 0 Degrees (ITCZ/Doldrums/Equatorial) Tropical Rainforest 20-35 Degrees (Horse lats ) Arid/Hot/Dry deserts 30-50 Degrees (Ferrel cell – mid-latitudes) Subtropical regions, Chapparal, Savannah, grasslands) 40-60 Degrees (Mid-latitides – sub-polar low) Moist continental climates, cold winters, warm summers Polar regions – warmest month below 10^C (average)

Atmospheric Circulation and Biomes Köppen Classification System: Wladimir Koppen a German botanist and climatologist studied and divided the Earth into climate regions using temp and precip statistics. 5 main divisions based on annual temperatures: A - Tropical Moist Climates: all months have average temperatures above 18° Celsius. B - Dry Climates: with deficient precipitation during most of the year. C - Moist Mid-latitude Climates with Mild Winters. D - Moist Mid-Latitude Climates with Cold Winters. E - Polar Climates: with extremely cold winters and summers.

Temperature vs. Precipitation

We start at the Equator……. As per the convective cell circulation model, our climate system and classification begins at the equator. Each hemisphere is generally symmetrical with minor differences based on altitude, terrain, distance from water, availability of sunlight, leeward/windward, jet stream location.

Tropical Rainforest Precipitation: 250cm rainfall per year Average temp = 77F (25’C) Daytime = 30-35C, Night time = 20-25C Daylight length – 12 hours Relative Humidity = 75% Why does this area have a large precipitation Link this to the latitude Link this to the elevation or topography Link this to the prevailing winds, wind speed and proximity to oceans (humidity) Length of day and exposure to Sun’s radiation

Desert (hot) Precipitation must be below 50 cm per year to qualify Many mean annual temperatures range from 20-25° C. The extreme maximum ranges from 43.5-49° C. Minimum temperatures sometimes drop to -18° C. Limited precipitation therefore limits the vegetation and domestic animal species Harsh environment causes specific adaptations to occur in order to be successful in this climate, terrain and conditions. Link this biome to: Why precipitation is low Why the prevailing winds are warm Climatic conditions causing a change from soil to sand The extent of such desert biome over a certain latitude

Chaparral/Grassland/Savanna These biomes are very similar in their temperature and precipitation (average per year): Chaparral: Mediterranean Climate (warm) Hot and dry summers Located between 30-50 Savannah: Tropical climate Winter dry season Grassland: Cold winters, long dry season Interior of continents 25% of world is covered by grasslands in different forms Chaparral Grassland Savannah Precipitation 25-43 cm 81cm 100-150cm Temperature 15C 31C 16-20C

Chaparral/Grassland/Savanna

Deciduous Forest Average temperature (annual) - 10’C 75-150 cm of precipitation annual Changes with the seasons Tilt influences this climate through fluctuating solar insolation and sun’s angle in the sky Has definitive growing seasons Is interacting with mid-latitude weather systems

Boreal Forest/Taiga Average range of temperate -5’C to 5’C. Particular latitudes dictate the amount and timing of precipitation. Range of 20cm to 200cm Controls certain vegetation and animal species Growing season is short Longer winters and sustained permafrost

Polar Desert (cold) Difference between Arctic and Antarctic Polar Regions: Land comparison (size of region): Arctic – 5.8 million square miles (fluctuates between summer and winter) Antarctic – 5.4 million square miles (land mass) + 6.9 – 1.1 million square miles of sea ice (fluctuates) Precipitation – less than 250mm annually Winter season: Arctic – 9 months of winter, short spring and fall Antarctic – jan/feb (summer), winter = april to oct Ice thickness: Arctic – 6ft (thinner – less dense) Antarctic – 3ft (thicker – dense) Temperatures (range): South Pole -60C to -28C North Pole -40C to 0C