ESYS 150 LECTURE 1 DISASTERS/POPULATION/ENERGY

1. ESYS 150LECTURE 1 DISASTERS/POPULATION/ENERGY Introduction Major Disasters Population Growth Earth Creation and Structure Energy Sources for Disasters

2. INTRODUCTIONDISASTERSEarthquake - Northridge 17 Jan 1994 Apartment building collapses on residents cars during the earthquake

3. INTRODUCTIONDISASTERSEarthquake: Kobe-Osaka 1995 Collapse of a freeway during the Kobe-Osaka earthquake 1995

4. INTRODUCTIONDISASTERSTsunami: Indian Ocean 2004

5. INTRODUCTIONDISASTERSVolcanic eruptions: Montserrat 1997 Soufriere Hills Volcano glows as hot sticky magma flows down the mountain in January. It blew as a huge pyroclastic flow in June

6. INTRODUCTIONDISASTERSFloods: Hurricane Mitch off Honduras 1998 Residents watch the river in flood in Honduras as a result of a hurricane stalling off the coast of Honduras and Nicaragua 27-29 October 1998

7. INTRODUCTIONDISASTERSComet collision: Hale Bopp 1997 Comet streaks above the telescope at Mauna Kea, Hawaii in 1997. Very unlikely any comet will hit the earth but when one does the effect will be catastrophic

8. INTRODUCTIONFREQUENCYRelationship of Magnitude to Frequency The greater the magnitude the rarer the event. The return time for an event of the same magnitude increases with the size of the event.

9. INTRODUCTION16 DEADLIEST DISASTERS 1970-2005Hurricanes, Earthquakes, Landslides

10. MAJOR DISASTERSTYPES The disasters which have caused the greatest number of fatalities over a long period are hurricanes, earthquakes and floods. Note most occur in Asia. Not equally distributed over Earth

11. MAJOR DISASTERSFATALITIES 1980-2005 Varies between 10,000 and 200,000 per year. However indication of an increase with date. Combination of better reporting and population increase on the Earth especially in Asia the most populous continent.

12. POPULATION GROWTHLAST 10,000 YEARS About 8 million 10,000 years ago. Following agricultural revolution and then the scientific medical revolution of the past 100 years the population has exploded. Birth rate has remained high whilst death rate dropped. 1.5 Billion 1900 doubled twice to 6.0 Billion by 2000. Not known where it will go from here

13. POPULATION GROWTHDOUBLING TIMES Rule of 70: Doubling time(yrs) = 70 / %growth rate per year At present 1.7% growth rate doubling time is 40 yrs. Will go to 12 billion by 2040. Scenario not as bleak as this. Rate is dropping.

14. POPULATION GROWTHWORLD WIDE POPULATION INCREASEProjected population in 2050

15. POPULATION GROWTHUNITED NATIONS ESTIMATES1994 to 2050 World population according to five different scenarios. The medium variant has dropped due to lower than expected fertility and the effect of the AIDS pandemic. Suggests population will max around 2050 at 8.9 Billion

16. POPULATION GROWTHANIMALS MULTIPLY TO EXHAUST FOOD SUPPLY Population curve shows fluctuation in detail. Good weather and plentiful supply gives upsurge. Bad weather, disease, scarcity gives downswing.

17. EARTH CREATION AND STRUCTURESOLAR SYSTEMDevelopment from a spherical cloud of gas, ice, dust etc

18. EARTH CREATION AND STRUCTURESOLAR SYSTEMFormation of Planets Starts as huge rotating spherical cloud of ice,gas, etc. The spinning mass contracts into a flattened disc with most of the mass at center. Planets grow as masses collide and stick together due to gravity. Solar radiation drove away gases and liquids from inner planets (Mercury, Venus, Earth and Mars) leaving behind rocky planets. The next four planets out (Jupiter, Saturn, Uranus and Neptune) are giant icy bodies of hydrogen, helium and other frozen materials

19. EARTH CREATION AND STRUCTURELAYERED EARTHEffect of differentiation The earth heats up melts and differentiates with the heavier iron and nickel descending to the core. Creates a density layered Earth, inner core, outer core, mantle and upper mantle.

20. EARTH CREATION AND STRUCTURELAYERED EARTHCrust and lithosphere The upper layers of the Earth can be viewed 1) as lower density crust separated from high density mantle, or, 2) As rigid lithosphere riding on top of a partially molten asthenosphere

21. ENERGY SOURCESINTERNAL HEAT Heat of formation and radioactive decay Major heat generating processes during the formation of the Earth include • Impacts of asteroids • Decay of radioactive elements • Gravitational contraction. Earth melts, differentiates and start to loose heat both conductively and through plate tectonics.

22. ENERGY SOURCESINTERNAL HEATPlate Tectonics The earth is a convective body and loses heat at the surface both by conduction and the creation of new plate. Creation and destruction of plate creates the rock cycle especially at subduction zones.

23. ENERGY SOURCESINTERNAL HEATCreates the constructive rock cycle Magma cools and solidifies to form igneous rock. Rocks at surface break down to sediments which form sedimentary rocks. With increasing pressure and temperature these sediments become metamorphic rocks. Heat melts the rocks which rise buoyantly to the surface and the cycle starts again.

24. ENERGY SOURCESEXTERNAL The Sun and Gravity: the Hydrologic Cycle The sun lifts water into the atmosphere by evaporation and transpiration. Atmospheric water condenses and falls under gravity. Water flows as glaciers, stream and groundwater to the seas. By returning sediment to the sea, this process destroys what the rock cycle constructs.