general science. population thomas malthus linearversusexponential

General Science

POPULATION

Thomas Malthus

Linear versusExponential

Population Numbers 1800

United States Population: 5,308,483

World Population: ~1,000,000,000

Where are We Today?

United States Population: 307,339,534

World Population: 6,781,576,663

World Vital Events 2007

Time Natural

Increase

Year 77,257,452

Month 6,438,121

Day 214,604

Hour 8,942

Minute 149

Second 2.5

Life Expectancy has changed over the years

Years USA Botswana

1970-1975 70.8 56.1

1975-1980 73.7 60.0

1980-1985 74.7 62.8

1985-1990 75.4 64.8

1990-1995 75.8 65.0

1995-2000

2000-2005

77.2

77.5

56.3

39.7

Life Expectancy at birth (2000-2005) source UN Statistics Division

Country Male Female Infant MR

U.S.A. 74.3 79.9 7

China 68.9 73.3 37

Japan 77.9 85.1 3

Zimbabwe 33.7 32.6 58

Sierra Leone 33.1 35.5 177

CLIMATE CHANGE

Natural Greenhouse Effect

Greenhouse effect Greenhouse gases

Source: Arctic Climate Impact Assessment 2004

Projected Surface Annual Air Temperature Changes 1990 - 2090

0C

+12C

+6C

Greenland Ice Sheet Melt

1992 2002

Projected Sea Level Rise

Projected Sea Ice Extent

2010 - 2030 2040 - 2060 2070 - 2090

Meeting the Climate Challenge January 2005Climate change represents one of the most serious and

far-reaching challenges facing humankind in the

twenty-first Century. The international consensus of

scientific opinion, led by the Intergovernmental Panel on

Climate Change, is agreed that global temperature is

increasing and that the main cause is the accumulation

of carbon dioxide and other greenhouse gases in the

atmosphere as a result of human activities. Scientific

opinion is also agreed that the threat posed will become

more severe over coming decades.

IPCC AR4 Synthesis Report 11/2007

Warming of the climate system is unequivocal, as is now evident from observations of increases in global

average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level

IPCC AR4 Synthesis Report 11/2007 North America • Warming in western mountains is projected to cause

decreased snowpack, more winter flooding, and reduced summer flows, exacerbating competition for over-allocated water resources;

• In the early decades of the century, moderate climate change is projected to increase aggregate yields of rain-fed agriculture by 5-20%, but with important variability among regions. Major challenges are projected for crops that are near the warm end of their suitable range or which depend on highly utilized water resources;

• During the course of this century, cities that currently experience heatwaves are expected to be further challenged by an increased number, intensity and duration of heatwaves during the course of the century, with potential for adverse health impacts;

• Coastal communities and habitats will be increasingly stressed by climate change impacts interacting with development and pollution.

CO2 Emissions 2006

Sea Ice sets New Record 9/16/07

OCEAN WORLDFish Catch

Biomass 1900 (tons/sq. km)

and in 2000

Reconciling Fisheries with Conservation:the Challenge of Managing Aquatic EcosystemsbyDaniel PaulySea Around UsFisheries Centre,University of British Columbia,VancouverFourth World Fisheries Congress,Vancouver, May 2-6, 2004

Net losses: Industrialized fishing hits fish stocks

Analysis of data from five ocean basins reveals a dramatic decline in numbers of large predatory fish (tuna, blue marlins, swordfish and others) since the advent of industrialized fishing. The world's oceans have lost over 90% of large predatory fish, with potentially severe consequences for the ecosystem. These findings provide indirect support for goals established at the UN's World Summit on Sustainable Development in Johannesburg last year. UN officials argued that three-quarters of the world's fisheries were fished to their sustainable limits or beyond, and made proposals for the restoration of depleted fisheries by 2015. Data on predatory fish are important as they are not dependent on datasets from commercial fisheries, which can be unreliable.