lecture 4: megatrends part ii - social. “humans are perhaps the most successful species in the...
TRANSCRIPT
Lecture 4: Megatrends Part II - Social
“Humans are perhaps the most successful species in the history of life on Earth. From a few thousand individuals some 200,000 years ago, we passed 1 billion around 1800, 6 billion in 1999”[, and 7 billion by the end of this year (2012).
Source: AAAS Atlas of Population and Environment (2000)
We have become a major force of evolution, not just for the "new" species we breed and genetically engineer, but for the thousands of species whose habitats we modify, consigning many to extinction; compelling others to evolve and adapt to our pressures. We have become a force of nature comparable to volcanoes or to cyclical variations in the Earth's orbit. ?Source: AAAS Atlas of Population and Environment (2000)
Thomas Robert Malthus
• "The power of population is indefinitely greater than the power in the earth to produce subsistence for man"
• An Essay on the Principle of Population, 6 editions published from 1798 to 1826.
• Noted that sooner or later population gets checked by famine and disease
World Population Trends
The world population increased from 3 billion in 1959 to 6 billion by 1999, a doubling that occurred over 40 years!
The annual increase in world population peaked at about 88 million in the late 1980s. The peak occurred well after the annual growth rates were past their peak in the late 1960s (because the world population was higher in the 1980s than in the 1960s).
Population Growth Rate Facts
• 1700: 600 million >>> 2003: 6.3 billion ….an order of magnitude increase.
• 1927: 2 billion• 1974 (<50yrs): 4 billion• 1999 (<25yrs): 6 billion
• Global Growth Rate peaked (2.1%/yr) between 1965-70.
Note: At the end of the 20th century the world average population density was 45 people per square kilometer
The 1998 projections from the UN Population Division trace three paths, largely depending on how fertility changes. The medium projection assumes that countries with fertility above 2.1 will not fall below that level, and countries with current fertility below 1.6 will rise again to between 1.6 and 1.9. The low projection allows fertility to fall more rapidly, to a floor of 1.6 in most countries, and to remain below that level where it is already below. The high projection assumes eventual stable fertility levels of 2.1 to 2.6 in all countries.
Population growth rates -- which determine the rate at which we must adapt our technology and institutions to avoid increasing environmental damage -- hit their highest 35 years ago, between 1965 and 1970, at 2.1 percent a year. In the current decennium they are projected to average only 1.2 percent a year.
Annual additions are important as they show the total numbers of new human beings the planet must provide with resources each year. These passed their peak more than a decade ago, at 86 million a year in the latter half of the 1980s. Currently they are running at some 75 million a year.
How current population growth is perceived depends very much on the data you look at. Popular approaches concentrate on total numbers (chart 1), which are important for our overall impact. These show a curve getting steeper from 1950 onwards, beginning to level out in 2050. We are currently on the steep section.
Age Distributions
There will be a dramatic "population explosion" of older people.
While the total population is projected to increase by only 40 percent between 2000 and 2050, the numbers of over-60s will rocket by 232%
Many current changes may raise morbidity and mortality…
• Antibiotics for example, lowered mortality rates, but there is concern that the spread of antibiotic-resistant bacteria may reverse this trend.
• Fertilizer use made great headway in providing sufficiently nutritious diets to lower mortality levels, but the environmental degradation resulting from overuse is deteriorating water quality and so raising mortality levels.
• Burning fossil fuels originally enabled a rapid growth in incomes, which improved nutrition, reduced mortality and accelerated population growth. But excess use of fossil fuels is driving global climate change, which may increase mortality by enlarging the zones susceptible to warm-climate diseases, and increasing the frequency of heat waves, storms, and flooding.
Adults and children estimated to be living with HIV, 2009
Total: 33.3 million (31.4 – 35.3)
The number of people living with HIV has risen from around 8 million in 1990 to 33 million today (2008), and is still growing. Around 67% of people living with HIV are in sub-Saharan Africa.
Number of newly infected with HIV, 1990 - 2009
Global HIV trends, 1990 - 2009
Changes in the incidence of HIV infection, 2001 - 2009
Global prevalence of HIV, 2009
Annual AIDS-related deaths by region, 1990 - 2009
Other Health Indicators
The Trend of Urban Living
The world is becoming increasingly urbanized, rising from
• 37% urban in 1970.
• 61% (projected) in 2030.
• Urban areas will see 95% of population growth between 1996 and 2030.
Megacities
Coastal Pollution Estimates show that almost 50% of the world's coasts are
threatened by development-related activities.
Too many people in/near coastal regions?
Katrina?
Ike?
Clean Water
• Clean water supplies and sanitation remain major problems in many parts of the world, with 20% of the global population lacking access to safe drinking water.
• Water-borne diseases from fecal pollution of surface waters continue to be a major cause of illness in developing countries.
• Polluted water is estimated to affect the health of 1.2 billion people, and contributes to the death of 15 million children annually.
Increasing Water Issues• It is estimated that two out of every three people will live in water-stressed
areas by the year 2025. In Africa alone, it is estimated that 25 countries will be experiencing water stress (below 1,700 m3 per capita per year) by 2025. Today, 450 million people in 29 countries suffer from water shortages.
Safewater Cartogram
An area cartogram is sometimes referred to as a value-by-area map
Global Economic Trends
The outlook for the world economy over the next 10 years is characterized by strong growth in almost all regions of the world. Impact on food imports and diet choices.
Global Economic Trends
Economic growth in developing countries is projected to average more than 5.6 percent annually during 2010-19. This compares with average growth in developed countries of 2.2 percent.
Consumption
The per-capita consumption of key natural resources varies hugely around the world. Typically, but not universally, the citizens of rich industrialized nations use more of the world's resources and produce more waste. Sometimes they thereby deplete their own environments; sometimes other people's
Consumption
As population growth is slowing, consumption growth is emerging as the dominant factor increasing our pressure on the environment.
Between 1980 and 1996…
• # of cars in the world increased from 320 million to 496 million, an annual growth rate of 2.8 percent
• # of TVs in the world grew from 561 million to 1.361 billion -- an average of 5.7 percent per year. Of this, the increase in television ownership levels accounted for 70 percent, and population growth for only 30 percent
FOOD CONSUMPTION
A typical example is meat. China, with the world's largest population, is the highest overall producer and consumer of meat, but the highest per-capita consumption in the world is that of the United States. The average United States citizen consumes more than three times the global average of 37 kilos per person per year
US Agriculture
US Agriculture
US Agriculture
US Agriculture
US Agriculture
Higher energy costs affect the agricultural sector more than the general economy. Energy-related costs are a relatively large share of non-farm input costs. Also, fertilizer prices will be up in 2001 due to high prices for natural gas, the major feedstock and boiler fuel in production of nitrogen-based fertilizer.
For the future of Africa, agriculture remains one of the most important issues. A majority of the population, especially outside urban areas, are involved in agriculture, and food security is one of the most important issues to solve in the short term in some parts of the region.
The current financial importance varies, as presented in this map, with agriculture representing up to 50-60% of the total economy in some countries (Guinea-Bissau, Central Africa, Ethiopia) and representing 20-40% in Sub-Saharan Africa.
A Sloping Playing Field
Land Transformation
We have transformed approximately half the land on Earth for our own uses
• 11% each for farming and forestry
• 26% for pasture
• At least another 2 to 3% for housing, industry, services and transport
• Area used for growing crops has increased by almost 6x since 1700, mainly at the expense of forest and woodland.
Reading Assignment
• Human Population Grows Up, Cohen (2005).