Population and Growth Rates - University of Hawaii at Hilo


Population and Growth Rates

Exponential growth rate of human population and the Doubling Time Limiters on population growth: farmland and food, non-food resources, carrying capacity of the earth?, large natural disasters and their effect on population Current Population between 6 and 7 billion people. CARRYING CAPACITY-ultimate sustainability of something (rivers for water and sediment, earth and people!) Resources Potentially renewable Non-renewable Perpetual Environmental Impact = # people x per capita resource use x degradation/pollution per unit

Earth Systems

Open, Closed, Isolated Lithosphere Pedosphere Biosphere Atmosphere Hydrosphere Energy System Feedback Mechanisms: Positive and Negative-characteristics of each Reservoirs in Earth Systems Flux, residence time (examples from hydrosphere, ocean water 2600 yrs, atmosphere 8 days, continent 400 years)

The Earth

Sources of Energy Internal: Radioactive decay (by far the most important), gravity, solar External: Solar (by far the most important), tides, gravity Layers of the earth Core/Mantle/Crust-names based on composition Inner core/outer core/mesosphere/asthenosphere/lithosphere-names based on physical properties Core made of Iron and Nickel Mantle made of heavier silicates and oxides (Mg and Fe rich) Crust made of lighter silicates and oxides Oceanic and Continental Crust Heat transfer and models of convection in the mantle, Temp. and Pressure changes Composition of the earth and space H and He are most abundant in the universe-formed from big bang-decrease with increasing atomic #. Fe (iron) most abundant in the earth

Si and O most abundant in the crust + Na, K, Ca, Fe, Al, Mg, Ti =most of crust