Lecture Outlines Natural Disasters, 5 th edition Patrick L. Abbott

Christiane Stidham, Stonybrook University Natural Disasters and the Human Population Natural Disasters, 5 th edition, Chapter 1

2003 Natural Disasters More than 83,000 people killed by natural disasters in 2003 Bam, Iran earthquake: 41,000 people –Gujarat, India (2001): 20,000 people –Izmit, Turkey (1999): 19,000 people –Tangshan, China (1976): 240,000 people European heat wave: more than 35,000 people –Unique event –Unprecedented temperatures, but probably more frequent with global warming

Human Fatalities in Natural Disasters Sawtooth-shaped curve caused by largest natural disasters Biggest killers (in order): hurricanes, earthquakes, floods, severe weather, landslides, volcanic eruptions, tornadoes and tsunami Most mega-killer disasters occur in densely populated belt through Asia, along Indian Ocean – number of fatalities is proportional to density of population Effects on survivors –Increase in suicides –Increase in altruism

Economic Losses from Natural Disasters Destruction and damage to structures, l oss of productivity and wages Increase in economic losses over time is result of increase in human population and urbanization Most expensive events caused by storms and occurred in U.S., Europe and Japan

Natural Hazards Hazard exists even where disasters are infrequent Evaluate site risk Mitigation prior to event –Engineering, physical, social and political plans and actions to reduce death and destruction from natural hazards Mitigation after event –Rebuilding and re-inhabiting same site –Case history: Popocatepetl Volcano, Mexico Eruptions in 822, 1519 and beginning again in 1994 Currently 100,000 people living at base

Magnitude, Frequency, and Return Period Inverse correlation between frequency (how often it occurs) and magnitude (how big it is) of a process –Frequent occurrences are low in magnitude, rare occurrences are high in magnitude –Small-scale activity is common, big events are rare –Larger the event, longer the return-period (recurrence interval) Cost-benefit ratio can be considered in conjunction with return- period of given magnitude event

The 20 th Century Was Unique Population growth at unprecedented and breathtaking rate, doubling twice Increased numbers of people in hazardous settings

Overview of Human Population History Difficult to assess early human population growth Human species ‘began’ approximately 160,000 years ago, with a few thousand people Human population has grown to 6.3 billion people in 2003 Growth rate is exponential

The Power of an Exponent of Growth Visualize in terms of doubling time –Number of years for population to double in size, given annual percentage growth rate –Doubling time = 70 % growth rate/year –Example of interest paid on money Linear growth: $ $100 / year Exponential growth: $ % / year –Example of water lily plant in pond Doubles in size every day Covers half the pond the day before it covers the whole pond

The Last 10,000 Years of Human History Flat population growth curve until 8,000 years ago –Agriculture established –Domestication of animals –Growth rate increased to 0.036%/year By 2,000 years ago, population ~200 million people –Better shelter, food and water supplies  faster population growth –Growth rate of 0.056%/year By 1750, population ~800 million people

The Last 10,000 Years of Human History By 1750, population ~800 million people –Establishment of public health principles, causes of disease recognized –Birth rates soared, death rates dropped By 1810, population ~1 billion By 1925, population ~2 billion By 1960, population ~3 billion By 1974, population ~4 billion By 1987, population ~5 billion By 1999, population ~6 billion By 2012, projected population ~7 billion

The Human Population Today Present population: (insert number) –Growth rate = 1.3%/year –Doubling time = 53 years Growth rate = fertility (birth) rate – mortality (death) rate

Future World Population Demographic transition theory: –Mortality and fertility rates decline from high to low levels because of economic and social development Population Reference Bureau estimates world population growth rates are dropping –From 1.8% in 1990 to 1.3% in 2003 –Due to urbanization and increased opportunities for women

Future World Population BUT population explosion continues –From 1950 to 2000 population grew from 2.5 billion to 6 billion –Growth rate of 1.3%/year means population of 9 billion in 2050 Consider no. of births / woman to predict 2150 population –Average 1.6 children/woman: 3.6 billion –Average 2 children/woman: 10.8 billion –Average 2.6 children/woman (current average): 27 billion

Mathematical Extrapolation Too many people? –Crowding in cities –Crime –Pollution –Illegal migration –Disease Room for more people? –Entire world population could fit inside 42 km x 42 km square carrying capacityConsider carrying capacity

Carrying Capacity How many people can Earth support? carrying capacity –Calculations of carrying capacity vary considerably –Increasing amounts of food can be produced –People can migrate from areas of famine or poverty to less crowded or wealthier areas –BUT Earth’s resources are finite, so solutions are temporary

Carrying Capacity Rapa NuiExample of Rapa Nui (Easter Island) –Isolated Pacific island with poor soil and little water –Settled by Polynesians in 5 th century Survived easily on chickens and yams, plenty of free time Developed elaborate competition between clans with moai (statues) –Civilization peaked at 1550, with population of about 7,000

Carrying Capacity Rapa NuiExample of Rapa Nui (Easter Island) –Reached by a Dutch ship in 1722 Found about 2,000 people living in caves Primitive society, constant warfare –Rapa Nui’s carrying capacity had been drastically lowered by society’s actions: Transportation of moai had required cutting down trees Erosion of soil made yams scarce Lack of canoes made fishing difficult and escape impossible

End of Chapter 1