Global Environmental Change

Global Environmental Change

Global Environmental
Change

Brian S. Schwartz, MD, MS
Johns Hopkins Bloomberg School of Public Health
Departmental of Environmental Health Sciences
July 29, 2011

1

Overview
• Contexts
• General definitions
• Key problems of GEC
• For each
– Problem definition and scope
– Some scientific evidence
– Health risks

2

© 2011. Johns Hopkins University
Except where attributed 1


Contexts

Sustainable Development
"Meeting the needs of the
Meeting
present generation without
compromising the ability of
future generations to meet
their needs."

Gro Harlem Brundtland, World Commission on
Environment and Development (Brundtland
Report) [subsequently became Director-General of
WHO], 1987
3

*

• Development: improving human condition in all
its aspects (economic, sociopolitical,
environmental)
• Sustainable development: by means and to
end points that are consistent with maintaining
improved conditions indefinitely
• Sustainable well-being: sustainable
development to achieve well-being where it is
p g
absent and putting the maintenance &
expansion of well-being onto a sustainable basis
where it is being provided unsustainably today

* Assistant to President Obama for Science & Technology, Director of White House
Office of S & T Policy, & Co-Chair of President’s Council of Advisors on S & T 4



Three Essential Pillars of Human
Well-being
• Economic conditions and processes
– Employment, income, wealth, markets, trade,
productive technologies
• Sociopolitical conditions and processes
– Law & order, national & homeland security,
g
governance, j justice, education, health care,
science, culture, arts, liberty, privacy
• Environmental conditions and processes
– Air, water, soils, mineral resources, biota,
nutrient cycles, climatic processes
5

The preservation and
enhancement of all three
are the core responsibilities
of societies

www.tahan.com

Nativeborncitizen.com

Texasliberal.com Corridors.conservation.org 6



Which of Three is Most Important?
• Each is indispensable
• Failure of any one can mean collapse of
y p
the human enterprise
• The three interact
– Economic systems cannot function without
inputs from environmental system or stability
provided by sociopolitical system
– Societal stability cannot be maintained in the
face of environmental disaster (even in the
most prosperous countries)
• Social disruption may be the main outcome of
concern
7

The world now faces
unprecedented threats to these
three pillars – arising from resource
limitations and uses – and thus to
human well-being.

This lecture is about trying to
y g
convince you about the existence
and magnitude of some of those
threats … 8



Environmental Signals at Global Level
• Atmospheric CO2 • Soil quality
• Temperature • Pasture lands
• Sea l
S levels l • Storm intensity
• Ecosystems • Forests
• Desertification • Rangelands
• Fisheries
• Glaciers
• Co a ee s
Coral reefs
• P l i caps
Polar ice
• Water tables
• Species losses
• Biodiversity
losses • Toxicants in air,
• Soil quantity water, soil
9

“We know from earlier
civilizations that the lead
indicators of economic
decline were environmental,
not economic. The trees went
first, then the soil, and finally
the i ili ti it lf To
th civilization itself. T
archeologists, the sequence
is all too familiar.”
10



Threat #1.
To all three pillars.
Peak oil and the
coming era of
energy scarcity
M. King Hubbert, 1903-1989. Geophysicist.
• He made a startling prediction first made public in 1949
prediction, 1949,
that the fossil fuel era would be of very short duration.
• In 1956 he predicted U.S. oil production would peak in
1970; he was scoffed at; he was exactly correct.
Our environment problem is mainly caused by energy; our energy
problem is mainly because there is not enough environment.
11

The bell-
shaped curve
of production
– Hubbert’s
Peak.

Hubbert’s original estimate
Scientific American, Energy and Power, 1971
Predicted world oil production would peak around 2000

It is a geologic reality that cannot be overcome with more
drilling or new technology 12



Oil-producing Countries Past Peak
Note: Hubbert’s
method worked
very well in 1956
to predict U.S.
peak in 1970

NGL = natural gas liquids
13

Monthly world oil production and prices, 2002–2010
World oil production has stalled
Flat from 2005-10 while demand increased 2-5%/year

Figure from Post Carbon Reader Ch 19 Data from US EIA



WSJ Blogs, Environmental Capital, 5/4/09
“Peak Oil: Global Oil Production’s Peaked”
(Raymond James, financial & energy investment services & analysis)
• Non-OPEC peaked in 2007
• OPEC and thus world, peaked in 1Q2008
OPEC, world
“… contention rests on simple argument: OPEC oil
production … fell … as oil prices were above $100
per barrel, a sign of the ‘tyranny of geology’ …”
“… a paradigm shift of historic proportions.”
Daily
production vs.
$ price

Oildrum.com

2003 2004 2005

2004

1997
2003
2005 2005

2005
2005

2006 2006
2006 2009

2007

2008
2009
2006 16



OVERVIEW

GLOBAL HEALTH

FOOD

CONFLICT
PUBLIC HEALTH DEPARTMENTS

URBAN FORM

COMMUNICATION

HEALTH CARE

17

Implications of Peak Oil Are Myriad
• Economies – high correlation between per
capita GDP and per capita energy inputs
• Food – our current system inefficiently converts
fossil f l i t f d
f il fuels into food
• Water – energy and water are inter-dependent
• Population – remarkable parallel between use
of fossil fuels and population growth
• Transportation – highly reliant on liquid fuels
• Communities and built environment
• Health – EMT, disaster preparedness and
response, hospitals, pharmaceuticals, plastics
• War – very dependent on liquid fuels
• Energy security – perhaps no such thing
18



“A Harsh Reality”
• “Oil: Peaking some time in the
next three years, possibly already
y y y
past peak
• Gas: Peaking some time in the
next three to 13 years
• Coal: Peaking some time in the
next 13 years
• Nuclear: Probably peaking some
time in the next 10 years, with lots 2008
of variables, but its use won’t
increase substantially”
19

Resource Scarcity
• Petroleum – as already covered; and energy
scarcity  minerals & materials scarcity
y y
• Fresh water – impacted by climate change
• Agricultural land – China purchasing prime
farmlands in Africa
• Phosphorus – US, China, Morocco possess
most of the resource, already limiting exports
• Rare earth elements – renewable energy
• Soil – loss of top soils due to farm practices
20



Related Problem.
Implications for all three pillars.

The U S has the “wrong” built
U.S. wrong
environment. We heavily invested in
a model that likely will be greatly
disruptive and disrupted in the 21st
Century,
Century and that is already affecting
public health in several ways.

I will tell you more about the built environment and
public health on August 8th. 21

The Key Threats to Pillars from Global
Environmental Change Are LINKED
• Global climate change (1) • Ecosystem destruction (3)
• Stratospheric O3 depletion (2) • Biodiversity & species loss (4)

… are caused by human behaviors & are a threat to health
1

2 3

WHO, 2006
4 3
22



Threat #2.
To all three pillars.

Climate
Change
Magnifi.co.uk

Unep.org
Lal.cas.psu.edu Asianet.fi 23

GALLUP POLL, April 21, 2008
National Journal, Oct. 2010: “The GOP is stampeding toward an absolutist
The
rejection of climate science that appears unmatched among major political
parties around the globe.”

Rasmussen Reports, June 28-29, 2009: 41% of Americans opposed (37% in
favor) to climate change and energy bill passed 219-212 along party lines in
U.S. House of Representatives last month, now being considered in Senate.

National Republican Congressional Committee: “Democrats ongoing crusade
against economic recovery.” 24



Timelines
• The planet is around 5B years old
• Humans have been in settlements for
around 10,000 years
• Industry and its hazards have been around
for approximately 200 years
• Global climate change has been a concern
for around 30 years (first world climate
conference in 1979, Kyoto Protocol 1997)
• Hottest year on record 2005; 2010 tied;
2009 2nd; 2000-9 hottest decade on record
• This happened fast!
25

26



Intergovernmental Panel
on Climate Change, 2007
IPCC was created in 1998; 2007 was fourth full report
p

“Most of the observed increase in
globally averaged temperatures
since the mid-20th century is very
likely due to the observed
increase in anthropogenic
greenhouse gas concentrations.”
27

Tim Flannery, Australian
mammologist, paleontologist, climate
activist: “… the pronouncements of the
IPCC do not represent mainstream
science, nor even good science,
but lowest-common-denominator
science – and of course even that
is delivered at glacial speed. If the
IPCC says something, you had
better believe it – and then allow
for the likelihood that things are far
worse than it says they are.”
28



• Analysis of air bubbles
in Antarctic ice cores A2
• Similar data for CH4
and N2O
• Atmospheric CO2 has
not exceeded 300 ppm B1
in 800,000 years

US GCRP, 2009 29

Northern Hemisphere Temperatures, Past 1,000 Years
“Multiple indicators, same bottom line conclusion:
consistent and unmistakable signal from the top of the
atmosphere to the bottom of the oceans”

30



A1F1

4°F / 2.2 °C

Observed and projected
O Simulated and projected
changes in global average changes in amount of
temperature, three IPCC precipitation in heaviest 5% of
scenarios, relative to 1960-79. days, relative to 1960-79.
A range of models predicts 2 More severe events are
to 11.5 °F. US GCRP, 2009
coming. 31

Momentum in Climate System and Lag Times: CO2, temperature,
and sea level continue to rise long after emissions are reduced

IPCC
32



US GCRP, 2009

A1F1

World CO2 emissions, 2008, 40%
higher than in 1990

Actual emissions have been worse
than even the most pessimistic IPCC
projection (A1F1) 33

Examples of global emission pathways for cumulative CO2
emissions of 750 Gt, 2010-2050 (an amount with 67%
probability of keeping global warming < 2°C).

If world population =
9B … this is
0.5T/person (US
current = 20T/person )

“An important consequence of the rapidly growing emissions rate … is that
any delay in reaching the peak in emissions drastically increases the
required rapidity and depth of future emissions cuts.” 34



Highlights
• 2010 one of two warmest years on record (2005)
• Weather extremes observed globally: hot, cold, wet, dry
• Arctic continues to warm at twice rate of lower latitudes
• Changes in ocean salinity patterns suggest increase in
hydrologic cycle
• Arctic sea ice extent third lowest on record since 1979
(Antarctic sea ice extent near maximum)
• Greenland glaciers lost more mass than in any year on
record (10 )
d (10y)
• Greenland Ice Sheet lost record mass (since 1958), area &
duration of melting largest since 1978
• Permafrost temperatures 2°C warmer than 20-30y ago
• 2010 is 20th straight year that alpine glaciers lost mass
• CO2 increased 2.6 ppm, higher than 30y average rate 35

How do we know these
changes are due to
human activities?

Detection and attribution research

36



IPCC, 2001; Hansen, 2011

Studying Climate
• Scientists study all this complexity using:
– Earth’s paleoclimate history: how did Earth respond to
past changes, especially in response to boundary forcings*
– M d
Modern observations of climate change, coincident with
b i f li h i id ih
rapidly-changing human-made & natural climate forcings
– Climate models and theory
• To project future climate:
– Use historical observations – paleoclimatology
– Use computer models
p
• Current data to develop and validate model, then use
to predict future
• Also use to understand perturbations – if current model
predicts current conditions well, perturb it to see how
this might change outcomes of interest
* Boundary forcings are factors that affect Earth's energy balance (e.g., solar irradiance, ice
sheet distribution, GHGs) 37

The Human Fingerprint

A climate forcing is an
imposed perturbation –
natural or human-made –
of Earth's energy balance

US GCRP, 2009 Forcings in Watts/m2 38



Stay < 2°C (3.8°F) increase, < 450 ppm CO2

“Catastrophic Climate Change”
• Sea level rise leading to
g
displacement of human populations
(10’s – 100’s millions)
• Extinction of 50% of plant and
p
animal species
• Regional climate change with large
impacts on food production and
hydrologic cycle
39

The Bad News About Climate Change
• GHG emission trajectories over past 7 years:
worse than even the worst IPCC projections
• In 2010, GHG emissions highest ever
• Ocean absorption of CO2 has been declining
• Ice sheet melting: much faster than predicted
• Coral reef bleaching accelerating
• Several tipping points in climate feedbacks
may soon be fully engaged – declining albedo,
burning boreal forests Amazon dieback
forests, dieback,
melting permafrost, enhanced El Niño
• Growing consensus: 450 ppm will not be safe;
need to get down to 350 ppm (now 390 ppm)
• To prevent < 2°C increase, emissions must
start declining by 2016 40



2007 Climate models are not needed to calculate
forcings – is about chemistry and physics.

Climate sensitivity (S) = equilibrium
global surface temperature change (ΔTeq)
in response to specified unit forcing after
planet has come back to energy balance
(S = ΔTeq/F).

Climate sensitivity depends upon climate
feedbacks – physical processes that occur
as climate changes in response to a forcing
0.75°C per W/m2 – that can enhance or diminish climate
3°C per 2xCO2 response.

> 2°C per W/m2 “Climate feedbacks are the core of
> 8°C per 2xCO2 the climate problem.”
Hansen J, 2011
41

Examples of policy-relevant tipping points (those that
could occur this century due to human activities)
Tipping point: critical threshold at which the future state of a system can be
qualitatively altered by a small change in forcing.

+

Others are not
depicted (e.g., shallow
water corral reefs) Copenhagen Diagnosis 42



Thawing permafrost above Arctic Circle
Methane 23X CO2

“The Peril Below the Ice” – A Positive Feedback

43

Impacts

2008 44



Temperature
Sea level rise
Precipitation

IMPACTS ON …
Species &
Water Coastal natural
Health Agriculture Forest resources areas areas

45

1. Global warming is unequivocal and
primarily human-induced
2. Climate changes are underway in the U.S.
and are projected to grow
3. Widespread climate-related impacts are
occurring now and are expected to increase
4. Climate change will stress water resources
5. Crop and livestock production will be
increasingly challenged
2009 46



6. Coastal areas are at increasing risk from
sea-level rise and storm surge
7. Risks to human health will increase
8. Climate change will interact with many
social and environmental stresses
9. Thresholds will be crossed, leading to
, g
large changes in climate and ecosystems
10.Future climate change and its impacts
depend on choices made today
2009 47

Climate Change & Public Health
• More heat-related illness
• Worsening air quality
• Rising sea levels
• More accidents and injuries from increased
flooding, storm surge, and extreme weather
• Greater risk of infectious diseases
• Threatened quantity & quality of water supplies
• Threatened food supplies
• Stressed ecosystems, potential for collapse, and
St d t t ti l f ll d
loss of ecosystem services
• Vulnerable populations
• Environmental refugees, social disruption,
conflict
48



Warmer Temperatures are Here
Heat-related morbidity and mortality – a direct
health effect of climate change
Nature 2004: Summers like this in Europe will
happen every other year by 2040

Summer 2003

35,000 dead
49

Example: Climate on the
Move – Changing Summers
Projections of summer average
temperature and precipitation changes
(mid = 2040 59 end = 2080 99)
2040-59, 2080-99)

Translates into considerably HOTTER
and DRIER summers in both locations.

Many other similar regional impacts
have been forecast: e g water levels
e.g.,
in Great Lakes, coastal erosion, insect
infestations, drought and flood risks

US GCRP, 2009 50



Conrad Icefield
and Glacier
Purcell Mountains
British Columbia

Melting, melting,
melting … 51

US GCRP, 2009
Conrad Icefield and Glacier
Purcell Mountains
British Columbia

Cubic miles of glacier ice loss

52



Retreating
Margin of
Larsen B Ice
Shelf, 1998-
2002

Red squares
indicate glacier
velocity
measurement
sites where speed
increased up to 5X
faster in 12 mo
after 2002 ice
shelf breakup
53

54



Rate of Greenland ice melting doubled
from 1996-2005

Moulin
(NASA photo)

55

Arctic Climate Impact Assessment 11/2004
Arctic Sea Ice

Observed September 1979
(first data) Observed September 2003
----------------------------- PROJECTIONS----------------------------
2010-2030 2040-2060 2070-2090

Telegraph, UK, Apr 2009: “Scientists say Arctic could
be ice-free within decade” 56



SoTC10: ARCTIC “Changes occurring faster
than in most of rest of world. Trends in snow
cover duration, permafrost, & vegetation
continued or accelerated.”

Updated to 2008 (Copenhagen Diagnosis)

2008
57

• IPCC: sea level projected
to rise 7-23 in by 2100*

• Hansen: paleoclimate data
suggest that sea l
t th t level will
l ill
rise > 20 ft (6 m) with 2°C 

* … excluding
future rapid
dynamical
changes in ice
flow & melting58



Rising Temperatures Warmer
temperatures
Worsen Air Pollution increase
tropospheric
ozone
formation

This has been
linked to
asthma and
cardiovascular
disease
hospitalizations
and deaths
59

Dengue
Malaria
Lyme disease

Some pests will thrive with change in
climate: vector-borne disease risk 60



Extreme Events
IPCC, 2007: Climate change will result in more
weather extremes – more heavy precipitation
events, floods, droughts, stronger hurricanes
(“climate chaos”)

• Regional extremes are very important to public health
• More relevant to people; largest impact on communities
•MMore difficult t model – greater variability on smaller
diffi lt to d l t i bilit ll
scales & resolution of current models an issue
• Much progress being made
• Regional extremes attribution improving and projections
are concerning
61

Katrina
3-day
average sea
surface T°

Yellow,
Yellow
orange, and
red areas are
> 82° F
(27.8° C, the
T° needed for
hurricanes to
strengthen).
Min 26° C
needed for
hurricanes to
form.

Epstein P. NEJM 2005; 353: 1433-6. 62



Hurricane projections to 2080 for 1%
annual increases in CO2 levels
63

Just As the Challenges of Peak Oil Arrive,
Climate Change Will Constrain Energy
Production
US GCRP, 2009:
• Energy production is likely to be
constrained by rising temperatures and
limited water supplies in many regions
• Energy production and delivery systems
are exposed to sea-level rise and
extreme weather events in vulnerable
t th t i l bl
regions
• Climate change is likely to affect some
renewable energy sources (e.g.,
hydropower)
64



2008

• Water is needed to generate energy – very
important and large quantities
• Energy is needed to deliver water
• These resources already limit the other –
increasing examples
• Switching from gasoline to electric vehicles or
biofuels is a strategic decision to switch
dependence from foreign oil to domestic water
• Complex inter-connectedness – our theme

Linkages
between
My sick joke is that Eastern Australia had average
rainfall for the last seven years. The first six were the
climate change,
driest six years in the record books, and the seventh
ecosystems,
was feet deep in unprecedented floods. Such y
“average” rainfall makes farming difficult. food
and
Jeremy Grantham, GMO LLC, May 2011 production

Meeting needs for increased
agricultural production has the
potential to increase global rates
of biodiversity loss, climate
change, & desertification. 66



Summers in 2080-2100 Warmer
than Warmest on Record
• Compared these
temperatures to historical ones
and their impacts on
agriculture
• Crop yields declined 20-50%
at these temperatures
• There will be food deficits in
many parts of world
• Tropics most susceptible
• Most of world lives in these
p
places
• Adaptation may help, must
start now

Using summer means (minimizes
tails, thus under-estimating effect)
67

An Equation for Disaster
Forced migration of millions

+ Scarce resources, including energy
+ Shrinking economies
+ Already stressed infrastructures and
ecosystems

= Conflict
• Wars over food, land, water, energy, environmental refugees?
• Each would have severe implications for population health.
68



Environmental Conflicts

TEEB, 2008 69

So, to review, and in summary …

70



71

2009 data
US: 5% population, 18% GHG emissions
72



Deaths Attributed to Climate
Change (selected outcomes only)

WHO data for 2000; for cardiovascular diseases, diarrhea, malaria, inland
and coastal flooding, and malnutrition.

In 2000 – 150,000 deaths Patz J, et al. Nature 2005; 438: 310-7.
73

1995 Nobel
Prize in
Chemistry

Stratospheric ozone
depletion
Some slides from Pyle JA, Solomon S. IPCC WG1, obtained from
http://arch.rivm.nl/env/int/ipcc/docs/SROCF/SBSTA22/01OzoneDepletion.pdf
July 19 2006
74



The Small Biosphere
Earth diameter = 8,000 Karman line (“edge of
miles space”) = 62 miles
Biosphere (layer in
which life can be found)
= 8 miles

Stratospheric ozone

Starryskies.com
75

Stratospheric Ozone
• Most O3 in lower stratosphere, 15-25
km
• Began accumulating 1-2B y agoago,
product of photosynthesis in aquatic
algae & plants
• O2 is converted to O3 by high-energy
photolytic action of UV radiation
– Cl* from CFCs catalyze breakdown of O3
Cl
• Ozone layer blocks out all UV-C, 50%
of UV-B, and small fraction UV-A*
• T1/2 for ozone regeneration: 3-4 y
* Wavelengths: UVA 400 nm - 320 nm; UVB 320 nm - 290 nm; UVC 290 nm - 100 nm 76



Chlorofluorocarbons (CFCs)
• DuPont, first synthesized 1928
• CFC-12 (R-12), DuPont trade name
( ),
Freon
– Primary use as refrigerant in
residential refrigerators and mobile air
conditioners
• CFC-11, 113, 114, 115 used in
production of other products
– Foam rubber (blowing agents), rigid
insulating foam, solvents in electronics
industry
77

CFCs and Ozone
• 1974: Molina & Rowland, two American
scientists, hypothesize CFC role in Nature
• 1978: U.S. bans use in spray cans
9 8 U S ba s sp ay ca s
• 1983: Scandinavians propose global ban
• 1985: Vienna Convention
– 20 nations sign; declaration, not commitment
– Precedent: multinational agreement on
environmental problem before clear scientific
consensus
– In 1985, there was no evidence that CFCs
actually damaged stratospheric ozone!
78



Potential Effects of Ozone Depletion
• Direct health effects
– SKIN: damage, cancer (10% loss, for 40
years, 300,000 new cases non-melanocytic
skin cancer, 5,000 9,000 new cases
cancer 5 000-9 000
melanoma)
– EYE: cataracts, conjunctival epithelial
thickening, ? retinal degeneration
– IMMUNE system: ? immunosuppression
• Indirect effects
– Crop yields, forest growth
– Phytoplankton reduction (under hole, 10% )
– Positive feedback to global warming (GW
increases ozone depletion which enhances
GW)
79

Regions of the world by latitude
90°

60°

30°

0°

30
30°

60°

90°
80



Early Observations
• 1985: British scientists – 40% loss of Antarctic ozone in late winter
and early spring
• 1986-7: losses reported over both poles, late winter
• 1988: inverse correlation measured between stratospheric CFC & O3
• 1980s: measured 50% increase in CFC levels
• 1988: new report, two important conclusions
– (1) Antarctic O3 hole caused by CFCs; and (2) O3  observed in
North Temperate Zone
– Industrial opposition to CFC phase out disappeared; DuPont
switches within 2 weeks
• 1980-92: at 30-50° N, O3 decreased 0.5%/y
• 1980s & 1990s: UV levels measured by satellite
– s of 5% per decade at 30° N and 30° S; 15% per decade at
55° S; 40% per decade over Antarctic; 10% per decade over
Arctic

81

Measured

82



So, good news for the world. But not all the news is good.
2/3 of world
total gone
by 2065

NASA simulation – a world without controls on Cl & B pollution
i l ti ld ith t t l Br ll ti

With controls, recovery was expected by 2050
“Amid the good news … lurk big questions about how long it
will take … A decade ago, researchers projected … fully
recover by 2050 … now … far more uncertainty. One …
complicating factor … GHGs have altered atmospheric
conditions … since Montreal Protocol was signed, some of
which speed up ozone recovery and some of which delay it.” 83

WMO & UNEP: > 700,000
excess cases 1980-2050 due
to ozone depletion

• MeBr pesticide still being used
(was supposed to be phased out by
2005 in developed countries), after
lobbying efforts
• Cl- and Br-containing compounds
in old air conditioners and fire-
fighting sys e s e pec ed to make it
g g systems expected o a e
to atmosphere as these break down
• Br levels in stratosphere are higher
than expected and than levels used
in models

84



World Response Summarized
• 1985: Vienna Convention
• 1987: Montreal Protocol on Substances that Deplete the
Ozone Layer
– 50% phase out of CFCs by 1998
• 1990: London Revisions
– Added new compounds, financial mechanisms for aiding
developing countries, added new control measures
• 1992: Copenhagen Amendment
– Added HCFCs, HBFCs, and MeBr
• 1997: Montreal Amendment
– Licensing systems for control & monitoring of substances
under agreements
• 1999: Beijing Amendment
– New compounds, new control measures, new restrictions
on trade
• Virtually all countries have ratified these treaties
85

Compare & Contrast
Ozone Depletion & Climate Change
• Both are global in scale
• Both pose significant potential risks to
inhabitants of this planet, both direct and
indirect
• Both with significant sources of uncertainty and
natural variability
• Both required complex computer modeling
• Both have generated considerable, rancorous
hh d d bl
debate
• One was “solved” before scientific consensus
• The other – the heated debate continues

86



Ecosystem
destruction

87

Millennium Ecosystem
Assessment
• 1400 experts from 95 countries
• S
Spent 4 years conducting a global
t d ti l b l
inventory of the state of our ecosystems
• Quantifying the effect that human
activities are having on them (and on
the impacts of ecosystem changes for
human well being)
well-being)
• Identifying information gaps
• Making suggestions for the future
• Results released April 2005
88



Millennium Ecosystem
Assessment Findings
• 60 per cent of the planet's
ecosystem services are currently
being degraded by human
activities
• 20 per cent of the world's coral
reefs have been lost
• 40 per cent of the planet's rivers
have been fragmented
89

Human Activities that Degrade
Ecosystems
• Runoff of pesticides, fertilizers, and
animal wastes
• Pollution of land, water, and air resources
• Introduction of non-native species
• Over-harvesting of fisheries
• Destruction of wetlands
• Erosion of soils
• Deforestation
• Urban sprawl
Ecological Society of
• Ecosystem fragmentation America, 2000
90



Ecosystem
Impacts
• Deforestation
• Coastal wetlands
• Marine fisheries
• Coral reefs
• Desertification

The coming era of
energy, water, and food
scarcity 91

Example: Marine Fisheries • Ocean acidification
• Over-harvesting • Pollution runoff from land
• Destructive practices • Warming oceans

2009

• Bottom trawlers with
enormous nets
• 20 lbs bykill for each
lb catch
• Up to 55% coral,
67% sponges
destroyed in single
drag
• Area larger than CA
already destroyed by
U.S. trawlers Seafloor destruction plume

Satellite view, Gulf of Mexico 92



Ecosystem Services Ecological Society of America, 2000
• Moderate weather extremes and impacts
• Disperse seeds
• Mitigate droughts and floods
• Protection from ultraviolet rays
• Cycle and move nutrients
• Protect streams, rivers, & coasts from erosion
• Detoxify and decompose wastes
• Control agricultural pests
• Maintain biodiversity
• Generate & preserve soils & renew fertility
• Contribute to climate stability
• Purify air and water
• Regulate disease carrying organisms
• Pollinate crops and natural vegetation 93

Images: nybooks.com

1921 2007

Mount Everest & Main Rongbuk Glacier, Tibet
Autonomous Region, China, 1921-2007

The “Third Pole” – Greater Himalayas and Tibetan Plateau: the largest non-
polar ice mass in the world
A critical ecosystem function: collect and store monsoon rains
Feeds ten major rivers in Asia: Yellow, Yangtze, Mekong, Salween,
Irrawaddy, Brahmaputra, Ganges, Indus, Amu Darya, and Tarim

Total flow from glacier melt: Indus 50%, Tarim 50%, Yangtze 18%, Salween 9%
But melt waters can account for up to 70% of spring and fall flows for each



Energy  Climate 
Ecosystems
• Energy issues, climate change, and
ecosystem issues are intricately
interlinked
• To date, our ecosystem issues
have looked less severe because
we have used cheap energy to
overcome
o e come them
• Climate change is now an
overarching set of challenges on
top of all ecosystem issues
95

Biodiversity and
species loss

96



First sighted RIP
Mauritius EXTINCT
c. 1580 c. 1681

The dodo bird
97
The first human-caused extinction

5 Mass Extinctions
• Ordovician Mass extinction:
– Cause: glaciation Earth loses 75%
of species in
• Devonian geologically short
– 70% of all species time interval
– Cause: global cooling
• Permian
– Largest extinction event
– 96% of all marine species, 75% of
terrestrial families
– Cause: Siberian volcanism & warming
• Triassic
– ~25% of all families, many vertebrates
– Cause:  CO2, warming, acidification
• Cretaceous
– Most famous – dinosaurs
– 85% of all species
– Cause: meteorite impact theory
remains the most probable 98



The 6th Mass Extinction
Caused by Humans
• >16,000 species currently threatened with
extinction
– 100 to 1,000 times the “normal” background
rate of species extinction
– In last 500 y, 844 extinctions due to human
activity
– Numbers of threatened species are increasing
• Different from previous
– No cataclysmic natural event
– Caused by humans

99

4

3
2

1

100



Mean Species Abundance

TEEB, 2008
1970 Arose out of G8+5 environment
ministers meeting in Potsdam,
FRG, May 2007

Major continuing
impacts, with additional
11% average losses
2050 2000-50, with > 20% in
some biomes, especially
in Africa, India, China.
(% of original land biodiversity) 101

Convention on Biological
Diversity
• Came from Earth Summit in 1992
– U.S. signed 1993
• The variability among living
organisms from all sources including
terrestrial, marine, and other aquatic
ecosystems and the ecological
complexes of which they are part.
This includes diversity within species,
between species and of ecosystems
(CBD, 2002).
102



Key Messages
• Biodiversity has many benefits for
humans
• Declines in biodiversity due to
human activities over the past 50
y have been rapid and
unprecedented in human history
• The main drivers of change are getting worse & are
likely to co t ue or accelerate
ey continue o acce e ate
• An unprecedented effort would be needed to
achieve (by 2010) a significant reduction in the rate
of biodiversity loss at all levels
103

104



The world’s ocean is at high risk of
entering a phase of extinction of marine
June 2011 species unprecedented in human history

Examined combined effects of pollution, acidification,
ocean warming, over-fishing, and hypoxia.
warming over-fishing hypoxia

The panel concluded that:

• The combination of stressors … is creating conditions
associated with every previous major extinction … in Earth’s
history
• The rate of degeneration … is far faster than … predicted
• Many … negative impacts previously identified are greater
than the worst predictions
• … the first steps to globally significant extinction may have
begun with a rise in the extinction threat to marine species
such as reef-forming corals
105

Bleaching as coral expel algae

Coral reefs: 0.2% of ocean floor; 25% of ocean’s biodiversity; key
source of protein for 500M people, protect coastal shores from
weather & tsunamis

World Resources Institute: 75% of world’s reefs at risk
Global Coral Read Monitoring Institute: 20% of world’s reefs lost

Warming seas, ocean acidification expected to put all world’s reefs at
risk by 2050



Parting Words
Climate change + energy scarcity:
the canvas on which the history of
h h h h h f
the 21st Century will be painted.*

Climate change is likely to be the predominant scientific,
economic, political and moral issue of the 21st century. The
fate of humanity and nature may depend upon early
recognition and understanding of human-made effects on
Earth's climate.
James E. Hansen, NASA Goddard Institute for Space Studies, 2011

* Adapted from Mark Lynas 107

“The Perfect Storm”
Challenges Responses Outcomes
Conflict
Ecosystem & The “wrong” built
Geopolitics of
species declines environment
scarcity Refugees
Climate change Deficits
Competition Social
The coming era of Huge fossil fuel over resources upheaval
energy scarcity inputs into food
production Population
Other resource
scarcity morbidity

Population
P l ti
mortality

(Workable
solutions) (Sustainability)

108



We the undersigned, senior members
of the world’s scientific community,
hereby warn all humanity what lies
ahead.
ahead A great change in our
stewardship of the earth and life on it is
required if vast human misery is to be
avoided and our global home on this
planet is not to be irretrievably
mutilated.
The World’s Scientists’ Warning to Humanity, 1992
(1,700 scientists signed, 104 Nobel laureates)
109

Australia, Saudi Arabia
2006
Brazil
1.9
Indonesia
1.6 Pakistan
0.8

Nigeria
0.6

Total emissions #1
#2

From 2002-2006, per capita emissions
increased from 2.1 to 4.6MT/y in China.
World average increased by ~15%. 110



An Editorial
• There is a lot we can do NOW with
technology … but not much happening
• While we are waiting for p
g political,
,
business, and public health leaders to
act …
• … what can WE do now?
• American behaviors are the biggest
cause of this problem
• The challenges presented today may b
h h ll d d be
the most difficult humanity has ever
faced
• The threats to human health and well-
being are potentially catastrophic
111

Which future
do you prefer?
Is this a false
choice or real?

Scientific American 2006 112



Remember:
We have
NOT EVEN
TRIED YET

113


Global Environmental Change

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