Chapter 1: Natural Disasters and the Human Population

Most frequent mega-killers have been…

Earthquakes and hurricanes

Most mega-killer disasters occur in a…

• Densely populated belt through Asia, along Indian Ocean

Number of fatalities is proportional to…

Density of population

Death totals are often related to

Economic and political factors

Destruction and damage to structures results in loss of

Productivity and wages

Disasters in 2016 cause what percent of global loss in GDP

0.24%

Increase in economic losses over time is result of

Increase in human population and urbanization

Highest insurance loses are caused by

Storms in U.S., Europe and Japan

How long does it take for total dollar losses to be known

Years

Hazard exists even where disasters are

Infrequent

Examples of mitigation measures taken after an event

• Engineering

• Physical

• Social

• Political

Mitigation examples after event

• Rebuild and re-inhabit same site

• Popocateptl Volcano, Mexico

How many people are currently living at the base of popocatepetl

100,000

What is the correlation between frequency and magnitude

Inverse

• Frequent occurrences are low in magnitude

• Rare occurrences high in magnitude

Another term for return period

Recurrence interval

How many years ago were there only a few thousand people on Earth

200,000

How many people living in 2017

1.7 billion (exponential pop growth currently)

Population growth was flat until how many years ago

8,000

• Agriculture established

• Domestication of animals

• Better shelter, food, water supplies

What percent per year has growth rate increased by

0.036%

2,000 years ago population 200 million people resulted in a growth rate of what percent per year

0.056%

By 1750 population was how many million people

800

Present population is over how many billion

7

What is the current growth rate per year

1.2%

What is the current doubling time in years

58 years

Growth rate formula

Fertility (birth) - mortality (death) rate

Human population grows by about how many million people per year

80 (roughly population of Germany)

Demographic Transition: before transition

High death rates offset by high birth rates to maintain population

Demographic Transition: During transition

Low death rates and high birth rates cause population to soar

Demographic Transition: After transition

Low death rates and low birth rates cause population to stabilize

In the past, earthquakes resulted in about how many million fatalities per century

1

Increasing the world population from 1.5 billion to 7.5 billion increased the risk of how many casualty earthquakes how many times

one million five times

Most population growth is concentrated in the cities of

Developing countries

• Poorly constructed buildings in mega-cities

• Million-death earthquakes are more likely

Pandemics are increasingly likely when

• Human and agricultural animal populations grow

• People move around globally via airplanes

How many million people did the Black Death kill in the 14th century in Europe

75 million

How many million people did Influenza A kill

50 million

How many COVID-19 deaths worlwide and how many in Canada

6.5 million deaths, 44k Canada

Example of carrying capacity

Ireland in 1840s

• Introduction of potatoes in 1500s led to population increase

• Potato blight resulted in one million deaths

• Potato increases carrying capacity and blight reduces it