Transcript State of the Planet

State of the Planet
“Executive Summary”
James G. Harris
Professor, EE Department and CPE Program
EE 563 Graduate Seminar
October 22, 2004
“The Blue Marble” Apollo 17 photograph (NASA)
Outline
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Background
Overview of State of the Planet
Summary of each of the eight papers
Conclusions
Reference websites
Background – Special Series
 Special report commissioned by Science to
assess state of planet now, and to give an
estimate for 2050
 Two articles per issue for four consecutive weeks
14 Nov. – 5 Dec. 2003
 Followed in 12 Dec. 2003 with special issue on the
publishing in Science of “Tragedy of the
Commons” by Garret Hardin 35 years ago
 This presentation is a brief summary of the eight
articles
Background – The Eight Papers
 “Human Population: The Next Half Century”
by Joel E. Cohen
 “Prospects for Biodiversity” by Martin
Jenkins
 “Tropical Soils and Food Security” by
Michael Stocking
 “The Future for Fisheries” by Daniel Pauly et
al
Background – The Eight Papers
 “Global Freshwater Resources: Soft-Path
Solutions for the 21st Century” by Peter
Gleick
 “Energy Resources and Global
Development” by Raymond J. Chow et al
 “Global Air Quality and Pollution” Hajime
Akimoto
 “Modern Global Climate Change” by
Thomas R. Karl and Kevin E. Trenberth
Overview of SOTP
 Eight areas represent the state of the planet
 Five common resources:
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Air
Fresh Water
Fisheries
Food and Soil
Energy
 Three key trends:
– Human population
– Biodiversity
– Climate
Overview of SOTP
 Personal observations
– Helps establish a defining set of variables for a
very complex system using scientific
perspective
– Engineering via computers, observation
systems (space and senor electronics), and
communications make SOTP possible
– Span of consideration 2000-2050 covers the
expected span of your careers
“Human Population: The Next Half
Century”
 Earth’s population grew from 600 M in 1700 to 6.3
B in 2003
– Order of magnitude growth in 300 years
 1965-70 global population growth rate reached its
all-time high of 2.1% per year
– 1.2% in 2002
 Demographics predictions for 2050 based upon
two UN sources:
– UN Population Division’s urbanization forecasts
– World Population Prospects: The 2002 Revision
“Human Population: The Next Half
Century”
 UN alternative projections include: low,
median, high, and constant-fertility variants
 Analysis based upon median variant
– Growth from 6.3B to 8.9B in 2050
– Comparison with historical growth rate:
 Beginning to 1800 for 1B growth in population
 13-14 years from now 1B growth
“Human Population: The Next Half
Century”
“Human Population: The Next Half
Century”
 Demographic uncertainties
– Migration and Families
 Migration
– From less to more developed countries
– 2.6M now declining to 2.0M in 2025-30 and remaining
constant
 Families
– Falling fertility
– Increasing longevity
– Changing mores of marriage, cohabitation, and divorce
“Prospects for Biodiversity”
 Consideration for biodiversity:
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Tropical forest
Temperate forest
Marine
Freshwater
 Assumptions:
– UN median population estimates for 2050: 6B to 9B by
2050
– Intergovernmental Panel on Climate Change scenario:
average surface temperature increases ~1-2º C and
CO2 increases ~100-200 ppm
– Humanity conducts affairs as a whole as currently
“Prospects for Biodiversity”
 Considerable number of species extinctions will
take place
 Existing large blocks of tropical forests reduced
and fragmented
 Temperate, and some tropical, forests will be
stable or increasing in area
 Marine ecosystems very different with few large
marine predators
 Freshwater biodiversity will be severely reduced
almost everywhere
“Prospects for Biodiversity”
“Prospects for Biodiversity”
 How much does it matter to human existence?
– Growing consensus humans directly or indirectly
responsible for extinction of all or most of large
terrestrial animal species
– Case of New Zealand: 38 species of flightless avifauna
reduced to 9 with few signs overall of terminal crisis to
humans
– Some point a threshold may be crossed, but likely
consequences from other factors such as abrupt climate
shift
“Tropical Soils and Food Security”
 UN Food and Agriculture Organization definition of
food security: “when all people, at all times, have
physical and economic access to sufficient safe
and nutritious food to meet their dietary needs and
food preferences for an active and healthy life”
 Currently,1B people without food security (1 in 6)
 60% of rural communities in tropics and subtropics
are persistently affected by decline in household
food production
“Tropical Soils and Food Security”
 Soil quality defined by Soil Science Society of
America: “the capacity of a soil to function within
land use and ecosystem boundaries, to sustain
biological productivity, maintain environmental
quality and promote plant, animal and human
health”
 Issue is ascribing decline in food production
unambiguously to soil quality
– Evidence of impact of soil quality on food production
growing
“Tropical Soils and Food Security”
“Tropical Soils and Food Security”
 Future in managing soil quality rests in
working with local communities
 Evidence of adaptability, flexibility, and
responsiveness to techniques that bring
private benefits to smallholders
 Providing simple provisions such as
adequately resourced extension services
and access to technology to smallholders
can transform food production
“The Future for Fisheries”
 Fisheries commonly perceived as local affairs
requiring annual reassessments of speciesspecific catch quota
 Past decade established fisheries components of
global enterprise on its way to undermining its
supporting ecosystems
 Future of fisheries
– Identification and extrapolation of fundamental trends
– Development and exploration with and without computer
simulation of possible futures
“The Future for Fisheries”
 Global fisheries landing declined about
500,000 metric ton per year from a peak of
80-85 million tons in the late 1980s
 Geographic and depth expansion of
fisheries easier to extrapolate
 Over past 50 years
– Bottom fishing went from 200 m to 1000 m
– Oceanic tuna, billfishes and relatives covered
the world ocean by the early 1980s
“The Future for Fisheries”
“The Future for Fisheries”
“The Future for Fisheries”
 Four future scenarios proposed by UN Environmental
Programme
– Market first: market considerations shape environmental policy
– Security first: conflicts and inequality lead to strong socioeconomic
boundaries between rich and pool
– Policy first: governments balance social equity and environmental
concerns
– Sustainability first: value system change favoring environmental
sustainability
 20-30% decrease and redistribution of current fishing effort
 Scenarios describe what might happen, not what will
happen
– Tragedy of the Commons
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
 20th century water policies relied on massive
infrastructure (dams, aqueducts, pipelines,
centralized treatment plants) to meet human
demands
– Hard-Path solution
 Serious unresolved water problems remain
– 1B people lack safe drinking water
– 2.4B people lack access to adequate sanitation services
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
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“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
 Soft-Path approach:
– Improve the productivity of water
– Delivers water services and quality matched to users’
needs
– Applies economic tools with goal to encourage efficient
use and equitable distribution
– Includes local communities in decisions about water
management, allocation, and use
 A fallacy of hard-path approach: using less water,
or failing to use more water, leads to loss of wellbeing
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
 Transition to soft-path already started
 Examples in US:
– Last two decades amount of water for toilets declined by
75%
– Proposed 67% reduction water use in California urban
areas without reduction in service
– Agriculture – farmers want to grow food and fiber, not
use water: use of drip irrigation
– Industry – semiconductor wafer water use went from 30
gal/in2 in 1970 to 6gal/in2 in 2003
 Conclusion: can’t follow both paths, must choose
“Energy Resources and Global
Development”
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Availability of global energy resources and their use
“Energy Resources and Global
Development”
“Energy Resources and Global
Development”
 Current rate of consumption (year 2000)
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Coal: .5% of reserves
Natural gas: 1.6% of reserves
Oil: 3% of reserves
Nuclear: 2% of reserves
 World not running out of mineral fuels
– But still finite amounts
 Possession of reserves not essential for development
– Japan: very little energy resources, but highly developed
– Nigeria: large oil reserves, but developing status
“Energy Resources and Global
Development”
 95% of annual energy consumption from fossil fuels
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44% petroleum
26% natural gas
25% coal
2.5% hydroelectric
2.4% nuclear
0.2% nonhydro renewable energy
 Higher GNP per capita generally implies higher efficiency
of energy use
 Cost of renewable energy not competitive at this time
“Energy Resources and Global
Development”
“Energy Resources and Global
Development”
 Growing concern for fossil fuel emission of
greenhouse gasses
 Given growing environmental concerns, future use
of fossil resources will change:
– Processes with increased efficiency
– Lower localized air pollution
– Carbon capture and sequestration
 Electricity generation will remain most important
use
– Generation flexibility
– Flexibility in use
“Energy Resources and Global
Development”
 Will world make transition to renewables?
– Simple answer – yes, when fossil costs rise
– Next 25-50 years, little transition expected
 If fossil fuel depletion occurs more rapidly
– Renewables and alternatives may come online more
quickly
 Requisite political will and financial support
required
– Benefits of fossil fuels do not make up for negative
effects on environmental health and human welfare
“Global Air Quality and Pollution”
 1986 report using MAPS satellite data established
that air pollution was an international issue
– Affected regional and global air quality
– Industrial fossil fuel burning from developed countries
– Biomass burning emissions from developing countries
 Recent satellite data confirms: GOME,
SCHIAMACHY, MOPITT, TOMS, TERRA
 Aerosol distribution also global in extent
 Surface ozone increasing
“Global Air Quality and Pollution”
“Global Air Quality and Pollution”
“Global Air Quality and Pollution”
 Pollutant atmospheric lifetimes long enough
to transport to other continents
– Order of 1 week for intercontinental transport
– Ozone: 1-2 weeks summer, 1-2 months winter
– CO 1-2 months
– Aerosols impact climate: 1-2 weeks
“Global Air Quality and Pollution”
 Megacities of greater than 10M people are
sources of regional and global pollution
– In 2001, 17 megacities according to UN
– Population growth and urbanization in future
 Local, regional, and global air-quality issues
should be viewed in integrated manner
– Regional and global environmental impacts
– Climate change
“Modern Global Climate Change”
 Planet Earth habitable because
– relative location to sun
– Natural greenhouse effect of its atmosphere
 Energy flow from sun
– Average energy at top of atmosphere 175 PW
– ~31% reflected from clouds and surface
– 120 PW absorbed by atmosphere, land, or ocean
 Ultimately emitted back to space as infrared radiation
– Infrequent volcanic eruptions have perturbed flow
– Inferred changes in total solar irradiance are small (0.2o
C in first half of 20th century; smaller later part)
“Modern Global Climate Change”
 Human influences on climate dominate
detectable influence for past 50 years
– Main impact on changes in atmospheric
composition (not actual heat generation)
– Estimated 1% change in energy flow to date
dominates all other human influences
 1 PW = 1million 1000 MW power stations
– Atmospheric composition changes due to
anthropogenic emissions of greenhouse gases
“Modern Global Climate Change”
“Modern Global Climate Change”
“Modern Global Climate Change”
 Absence of climate mitigation policies, 1.7o to 4.9o
C is 90% probability interval for warming from
1990 to 2100
– More frequent heat waves, droughts, extreme
precipitation events
– Related regional impacts: wild fires, vegetation changes,
sea level rise
 Rate of human-induced climate change projected
to be faster than natural processes, e.g., 10,000
year cycle ice ages
– Irreversible thresholds likely exist
 Climate change guaranteed in future
Conclusions
 Five common resources:
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Air: pollution is global, not local, problem
Fresh Water: efficient use of water, not produce more water
Fisheries: tragedy of the commons problem
Food and Soil: local solutions to efficiently produce food and fiber
Energy: market forces will most likely cause change from fossil fuel
dependency
 Three key trends:
– Human population: ~50% more people by 2050 (6B to 9B)
– Biodiversity: less diversity, but impact to human life on the planet
less than other factors
– Climate: human impact on atmosphere growing in significance with
unknown consequences
URL for “State of the Planet
 Web site available for all articles comprising
the “State of the Planet”, and the “Tragedy
of the Commons”
– http://www.sciencemag.org/sciext/sotp/
– Not complete access (AAAS members)
 EE 563 student PowerPoint presentations
for the eight articles are available:
– http://www.calpoly.edu/~jharris/courses under
EE 563 Winter 2003
Tropical Soils and Food Security
The Future for Fisheries
 Use UN Environmental Programme four
scenarios to investigate future of fisheries
– Market first
– Security first
– Policy first
– Sustainability first
“Global Air Quality and Pollution”
“Global Freshwater Resources:
Soft-Path Solutions for the 21st Century”
“Energy Resources and Global
Development”
 Consequences of the global distribution and
use of energy resources
 Estimate of future