BIOGEOGRAPHY GEO 4300/5107C The Environmental Setting (Geographic Template) Lecture 3: 8 January 2015
Last Time Topics and Subdisciplines of Biogeography History of Biogeography Western biogeography first written record in Classical Greece; Great Islamic Geography Exploration reports beginning 14 th Cent. (Marco Polo) Intellectual change to idea of mutability of Earth and biota in very late 18 th, early 19 th Cent. Biogeographic Laws late 19 th, first half 20 th Cent. Theoretical and Technological innovation second half 20 th Cent. Need for understanding in Conservation, Climate Change
This Time: Systematics and The Environmental Setting Life and Levels of Organization Systematics and Biological Nomenclature Present day vs. long-term Climate Energy Atmospheric Circulation Patterns Climatic Regions of the World Precipitation Temperature Life Zones Soils Parent Materials Soil Formation Aquatic Environments Microenvironments
Lomolino et al. Page 47 The most obvious patterns in the distributions of organisms occur in response to variations in the physical environment. Terrestrial: climate (temperature and precipitation) and soil type. Aquatic/Marine: water temperature, salinity, light, and pressure.
Main Point for Biogeography Environment is variable in both space and time, and for all variables Environmental factors create gradients of tolerance and optimality for organisms. E.g. light, ph, temperature, salinity, etc. We must understand how environment varies.
The Geographic Template: Structure Environmental conditions vary in a highly non-random manner across geographic gradients of latitude, elevation, depth, and proximity to major landforms such as coastlines and mountain ranges. Lomolino et al. p. 48
The Earth System Atmosphere Hydrosphere Geosphere, or Lithosphere Biosphere Borrowing from R. Christopherson. 2008. Geosystems. Prentice-Hall.
Understanding Energy - Absorbing and Emitting Radiant Energy: Black-body Radiation Short-wave - visible and infrared, but not detectable by feel. Long-wave - feels hot Ideal black body absorbs all energy from incident radiation, and emits all energy that it receives.
Earth as a good black-body radiator: Solar and Terrestrial Energy Distribution by Wavelength
Shortwave Radiation, Longwave Radiation, and Earth s Energy Budget.
Uneven Distribution of Insolation Subsolar Point Sphericity, inverse square law, atmospheric thickness
Insolation solar radiation on the Earth s surface. Insolation and Net Energy Balance at Earth s Surface W m -2 (note 1 W m -2 = 2.064 cal cm -2 s -1 ) Net incoming (shortwave) energy minus outgoing (longwave thermal) energy.
Insolation and Seasons Daily Insolation Received at the Top of the Atmosphere (Watts / m 2 / day) Profiles Solar Constant = 1372 W m -2 but varies with sunspot density
Geographic Controls of Temperature 1. Altitude 2. Latitude 3. Cloud Effects 4. Land-Water Heating Differences
Land-water Heating Differences 540 cal g -1 water ~0.25 cal/g for 1 C change ~1 cal/g for 1 C change
Latitude and Temperature Generally: 1. Decrease in mean temp with latitude 2. Increase in seasonality with latitude 3. But note effect of proximity to oceans (Edingurgh). Figure 5.4
Continentality
Global Temperatures for January Isolines Isotherms
Global Temperatures for July
Global Annual Temperature Range
VERY IMPORTANT RULES! 1. Warm air rises 2. Rising air expands 3. Expanding air cools 4. Cooler air holds less moisture 5. And vice-versa
Global Net Heat Distribution
Three Physical Forces that Produce Winds Pressure Gradient Pressure Gradient + Coriolis Forces Pressure Gradient + Coriolis Forces + Friction Forces
Global Wind Circulation, Hadley Cells
Global Barometric Pressure in January Isobars
Global Barometric Pressure in July
Global Patterns of Pressure
General Atmospheric Circulation
Clouds Show Circulation Patterns Source: http://www.ssec.wisc.edu/data/comp/latest_moll.gif
Global Vegetation Distribution
Understand Temperature and Precipitation at Global Scale Next Time A Little More Climate Soils Aquatic Ecosystems