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Global Environmental Change

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Title: Global Environmental Change


1
Introduction
  • Global Environmental Change Lecture 1 Spring
    2015

2
Why Global Environmental Change?
  • This course was designed as a climate change
    course, yet the name chosen was Global
    Environmental Change WHY?

3
Speculation
  • People have speculated that human activities
    might influence the environment
  • The Greeks, and later others, thought that forest
    cutting might influence rainfall, but there were
    disagreements about whether the influence would
    be positive (more rainfall) or negative

4
Ice Ages
  • When it was discovered that the earth had once
    been covered with ice, the obvious questions
    concerned the cause
  • Possible causes
  • Variations in the heat of the Sun?
  • Volcanoes erupting clouds of smoke?
  • The raising and lowering of mountain ranges,
    which diverted wind patterns and ocean currents?
  • Changes in the composition of the air itself?
  • Or?

5
Mans Effects
  • In 1827, Jean Baptiste Joseph Fourier, a French
    mathematician, suggested that gases in the
    earths atmosphere might absorb infrared
    radiation and influence earths climate
  • He made an analogy to a greenhouse, although the
    name greenhouse effect came much later
  • In 1896, Swedish scientist Svante August
    Arrhenius published a paper in which he
    calculated the effect of carbon dioxide in
    heating the earth more about this later

6
Callendar Effect
  • By the 1930s, it was discovered that the United
    States and North Atlantic region had warmed
    significantly during the previous half-century
  • Guy Stewart Callendar (1898 - 1964), an English
    steam engineer and inventor, developed a theory
    that linked rising carbon dioxide concentrations
    in the atmosphere to global temperature
  • Although previously discussed by Fourier,
    Arrhenius, and others, the effect is sometimes
    called the Callendar effect, because Callendar
    insisted that warming was on its way

G.S. Callendar, 1934
7
Scientific Investigation
  • Callendars claims did provoke scientific
    investigation
  • At the suggestion of Roger Revelle, Charles David
    Keeling began measuring carbon dioxide and,
    later, other greenhouse gas concentrations in the
    atmosphere, starting in 1957
  • It was quickly discovered that CO2 levels were
    increasing

8
Credit
  • Much of the remainder of this lecture is based on
    Discovery of Global Warming site created by
    Spencer Weart, with initial support from the
    American Institute of Physics, the National
    Science Foundation and the Alfred P. Sloan
    Foundation
  • http//www.aip.org/history/climate/impacts.htmimp
    acts

9
Scientific Progress
  • Simple mathematical models of the climate were
    developed
  • Feedbacks that could make the system surprisingly
    variable were discovered
  • Ingenious ways to retrieve past temperatures by
    studying ancient pollens and fossil shells were
    developed
  • Apparently, grave climate change could happen,
    and in the past had happened, within as little as
    a few centuries
  • Computer models of the general circulation of the
    atmosphere, the fruit of a long effort to learn
    how to predict (and perhaps even deliberately
    change) the weather, reinforced this finding

10
1960s
  • Calculations. made in the late 1960s, suggested
    average temperatures would rise a few degrees
    within the next century
  • Groups of scientists that reviewed the
    calculations
  • They were thought to be plausible
  • No need for any policy action, aside from putting
    more effort into research to find out for sure
    what was happening , was regarded as necessary,
    since the next century was a long way off

11
1970s
  • The rise of environmentalism raised public doubts
    about the effects of human activity on the planet
  • Curiosity about climate turned into anxious
    concern
  • Greenhouse effect concerns
  • Some scientists pointed out that human activity
    was putting dust and smog particles into the
    atmosphere, where they could block sunlight and
    cool the world
  • Analysis of Northern Hemisphere weather
    statistics showed that a cooling trend had begun
    in the 1940s and was continuing

12
Confusion
  • The mass media were confused
  • Sometimes predictions of a balmy globe, with
    coastal areas flooded as the ice caps melted,
    were given
  • Sometimes the media warned of the prospect of a
    catastrophic new ice age
  • Study panels, first in the U.S. and then
    elsewhere, began to warn that one or another kind
    of future climate change might pose a severe
    threat
  • Scientific agreement was limited to saying
    scientists scarcely understood the climate
    system, and much more research was needed

13
Increasing Research Activity
  • Research activity did accelerate, including huge
    data-gathering schemes that mobilized
    international fleets of oceanographic ships and
    orbiting satellites
  • Scientists were coming to understand that climate
    is an intricate system responding to a great many
    influences
  • Volcanic eruptions and solar variations were
    still plausible causes of change, with some
    arguments that these would swamp any effects of
    human activities
  • Even subtle changes in the Earth's orbit could
    make a difference
  • To the surprise of many, studies of ancient
    climates showed that astronomical cycles had
    partly set the timing of the ice ages

14
Chaos
  • The climate appeared to be so delicately balanced
    that almost any small perturbation might set off
    a great shift
  • According to the new "chaos" theories, in such a
    system a shift might even come all by itself ,
    and very suddenly
  • Support for the idea came from ice cores
    arduously drilled from the Greenland ice sheet,
    which showed large and disconcertingly abrupt
    temperature jumps in the past

15
Late 1970s
  • Global temperatures began to rise again
  • Many climate scientists had become convinced that
    the rise was likely to continue as greenhouse
    gases accumulated
  • One unexpected discovery was that the level of
    certain other gases was rising, which would add
    seriously to global warming
  • Some of these gases also degraded the
    atmosphere's protective ozone layer, and the news
    inflamed public worries about the fragility of
    the atmosphere

16
1980s
  • Greatly improved computer models began to suggest
    how dramatic climate jumps could happen, for
    example, through a change in the circulation of
    ocean currents
  • Experts predicted
  • Droughts
  • Storms
  • Rising sea levels
  • Other disasters
  • Politicians began to suspect there might be a
    public issue here

17
Beginnings of the Model Controversies
  • Modelers had to make many arbitrary assumptions
    about clouds and the like, and reputable
    scientists disputed the reliability of the
    results
  • Others pointed out how little was known about the
    way living ecosystems interact with climate and
    the atmosphere
  • For example, what were the effects of agriculture
    and deforestation in adding or subtracting carbon
    dioxide from the air
  • One thing the scientists agreed on was the need
    for a more coherent research program
  • By around 2000, some predicted, an unprecedented
    global warming would become apparent 

18
1988
  • In the summer of 1988, climate scientist's
    worries first caught wide public attention
  • The summer of 1988 was the hottest on record
    till then
  • An international meeting of scientists warned
    that the world should take active steps to cut
    greenhouse gas emissions
  • James Hansen spoke out, becoming a powerful voice
    urging both climate research and efforts to
    reduce carbon dioxide emissions

19
Beginnings of Climate Wars
  • Corporations and individuals who opposed all
    government regulation began to spend many
    millions of dollars on lobbying, advertising, and
    "reports" that mimicked scientific publications,
    in an effort to convince people that there was no
    problem at all
  • Environmental groups, less wealthy but more
    enthusiastic, helped politicize the issue with
    urgent cries of alarm
  • Many scientific uncertainties, and the sheer
    complexity of climate, made room for limitless
    debate over what actions, if any, governments
    should take

20
Early 1990s
  • Was the global temperature rise due to an
    increase in the Suns activity?
  • Solar activity began to decline, but the
    temperature soared faster than ever
  • Did computer models reproduce the present climate
    only because they were tweaked until they matched
    it, making them worthless for calculating a
    future climate change?
  • Improved models successfully predicted the
    temporary cooling due to a huge volcanic
    explosion in 1991 and passed many other tests
  • In particular, the modelers could now reproduce
    in detail the pattern of warming, changes in
    rainfall, etc. actually observed in different
    regions of the world over the past century
    (hindcasting)

21
State of the Climate Models
  • Modeling teams that made different assumptions
    about the physics of clouds and pollution got
    somewhat different results
  • Most of them found a warming of around 3C when
    the carbon dioxide level doubled, late in the
    21st century
  • Some found a rise of 2C or perhaps a bit less,
    costly but probably manageable
  • Others calculated a 5C rise or even more, an
    unparalleled catastrophe

22
Antarctic Ice Cores
  • For hundreds of thousands of years, carbon
    dioxide and temperature had been linked anything
    that caused one of the pair to rise or fall had
    caused a rise or fall in the other
  • It turned out that a doubling of carbon dioxide
    had always gone along with a 3C temperature
    rise, give or take a degree or two
  • This provided striking confirmation of the
    computer models, from independent geologic
    evidence

23
Response Creation of IPCC
  • It was established by the United Nations
    Environment Programme (UNEP) and the World
    Meteorological Organization (WMO) in 1988 to
    provide the world with a clear scientific view on
    the current state of knowledge in climate change
    and its potential environmental and
    socio-economic impacts
  • In the same year, the UN General Assembly
    endorsed the action by WMO and UNEP in jointly
    establishing the IPCC

24
What is IPCC?
  • The IPCC is a scientific body under the auspices
    of the United Nations (UN)
  • It reviews and assesses the most recent
    scientific, technical and socio-economic
    information produced worldwide relevant to the
    understanding of climate change
  • It does not conduct any research nor does it
    monitor climate related data or parameters

25
IPCC Reports
  • IPCC began to publish assessment reports
  • First Assessment Report (FAR) 1990
  • Second Assessment Report (SAR) 1995
  • Third Assessment Report (TAR) 2001
  • Assessment Report 4 (AR4) 2007
  • Assessment Report 5 (AR5) 2013

26
IPCC Progress
  • The world's governments had created a panel to
    give them the most reliable possible advice, as
    negotiated among thousands of climate experts and
    officials.
  • By 2001, the Intergovernmental Panel on Climate
    Change (IPCC) managed to establish a consensus,
    phrased so cautiously that scarcely any expert or
    government representative dissented
  • The IPCC announced that, although the climate
    system was so complex that scientists would never
    reach complete certainty, it was much more likely
    than not that our civilization faced severe
    global warming
  • The discovery of global warming was essentially
    completed

27
2000 a New Millennium
  • Scientists knew the most important things about
    how the climate could change during the 21st
    century
  • How the climate would actually change now
    depended chiefly on what policies humanity would
    choose for its greenhouse gas emissions

28
2000s
  • Greatly improved computer models, together with
    an abundance of data of many kinds, strengthened
    the conclusion that human emissions are very
    likely to cause serious climate change
  • The IPCC's conclusions were reviewed and endorsed
    by the national science academies of every major
    nation from the United States to China, along
    with leading scientific societies and indeed
    virtually every organization that could speak for
    a scientific consensus
  • Specialists meanwhile improved their
    understanding of some less probable but more
    severe possibilities

29
James Lawrence Powell Pie-Charts
30
New Findings
  • Dangerous change in ocean circulation seemed
    unlikely in the next century or two
  • There were signs that disintegrating ice sheets
    could raise sea levels faster than most
    scientists had expected
  • Worse, new evidence suggested that the warming
    was itself starting to cause changes that would
    generate still more warming

31
Beginning of the 2010s
  • Scientists who had been predicting for decades
    that, by 2000, the world would be significantly
    warmer were now obviously correct
  • Science reporters, business leaders, government
    advisers and others increasingly believed them
  • An ever larger number of individuals, corporate
    entities, and government agencies at every level
    decided that something had to be done

32
Likely Consequences
  • Likely consequences of restrained warming, by two
    or three C
  • What we may expect if humanity manages to begin
    restraining its emissions soon, so that
    greenhouse gases do not rise beyond twice the
    pre-industrial level

33
Anticipated Changes - 1
  • Most places will continue to get warmer
  • Especially at night and in winter
  • Temperature change will benefit some regions
    while harming others
  • Patterns of tourism will shift
  • Warmer winters will improve health and
    agriculture in some areas
  • Globally, mortality will rise and food supplies
    will be endangered due to more frequent and
    extreme summer heat waves and other effects
  • Regions not directly harmed will suffer
    indirectly from higher food prices and a press of
    refugees from afflicted regions

34
Anticipated Changes - 2
  • Sea levels will continue to rise for many
    centuries
  • The last time the planet was 3C warmer than now,
    the sea level was at least 6 meters (20 feet)
    higher
  • That submerged coastlines where many millions of
    people now live, including cities from New York
    to Shanghai
  • The rise will probably be so gradual that later
    generations can simply abandon their parents'
    homes, but a ruinously swift rise cannot be
    entirely ruled out
  • Storm surges will cause emergencies

35
Anticipated Changes - 3
  • Weather patterns will keep changing 
  • Toward an intensified water cycle with stronger
    floods and droughts
  • Most regions now subject to droughts will
    probably get drier (because of warmth as well as
    less precipitation), and most wet regions will
    get wetter
  • Extreme weather events will become more frequent
    and worse
  • In particular, storms with more intense rainfall
    are liable to bring worse floods
  • Some places will get more snowstorms, but most
    mountain glaciers and winter snowpack will
    shrink, jeopardizing important water supply
    systems
  • Each of these things has already begun to happen
    in some regions

36
Anticipated Changes - 4
  • Ecosystems will be stressed 
  • Although some managed agricultural and forestry
    systems might benefit in the first decades of
    warming
  • Uncounted valuable species, especially in the
    Arctic, mountain areas, and tropical seas, must
    shift their ranges
  • Many that cannot will face extinction
  • A variety of pests and tropical diseases are
    expected to spread to warmed regions
  • These problems have already been observed in
    numerous places

37
Anticipated Changes - 5
  • Increased carbon dioxide levels will affect
    biological systems, independent of climate change
  • Some crops will be fertilized, as will some
    invasive weeds (the balance of benefit vs. harm
    is uncertain)
  • The oceans will continue to become markedly more
    acidic, gravely endangering coral reefs, and
    probably harming fisheries and other marine life

38
Anticipated Changes - 6
  • There will be significant unforeseen impacts
  • Most of these will probably be harmful, since
    human and natural systems are well adapted to the
    present climate
  • The climate system and ecosystems are complex and
    only partly understood, so there is a chance that
    the impacts will not be as bad as predicted
  • There is a similar chance of impacts grievously
    worse than predicted

39
Climate Denial
  • Others insisted that the IPCC was wholly
    mistaken there was no need to worry
  • A minority of scientists (scarcely any of them
    known for contributions to climate science) who
    held to the old conviction that human activity
    was too feeble to sway natural systems
  • Distrust of the climate experts was encouraged by
    corporations and political interests that opposed
    any government interference in the economy

40
Representative Concentration Pathways
  • Scenarios that include time series of emissions
    and concentrations of the full suite of
    greenhouse gases (GHGs) and aerosols and
    chemically active gases, as well as land use /
    land cover
  • The word representative signifies that each RCP
    provides only one of many possible scenarios that
    would lead to the specific radiative forcing
    characteristics
  • The term pathway emphasizes that not only the
    long-term concentration levels are of interest,
    but also the trajectory taken over time to reach
    that outcome

41
RCP 2.6
  • One pathway where radiative forcing peaks at
    approximately 3 W m2 before 2100 and then
    declines (the corresponding ECP assuming constant
    emissions after 2100)
  • Corresponds to concentrations of 450 ppm CO2eq

42
RCP 4.5
  • Intermediate stabilization pathways in which
    radiative forcing is stabilized at approximately
    4.5 W m2 after 2100 (the corresponding ECPs
    assuming constant concentrations after 2150)
  • Corresponds to concentrations of 650 ppm CO2eq

43
RCP 6.0
  • Intermediate stabilization pathways in which
    radiative forcing is stabilized at approximately
    6.0 W m2 after 2100 (the corresponding ECPs
    assuming constant concentrations after 2150)
  • Corresponds to concentrations of 850 ppm CO2eq

44
RCP 8.5
  • One high pathway for which radiative forcing
    reaches greater than 8.5 W m2 by 2100 and
    continues to rise for some amount of time (the
    corresponding ECP assuming constant emissions
    after 2100 and constant concentrations after
    2250)
  • Corresponds to concentrations of 1370 ppm CO2eq

45
Scenario Constraints
  • Scenarios of how the future develops without
    additional and explicit efforts to mitigate
    climate change (baseline scenarios) and with
    the introduction of efforts to limit GHG
    emissions (mitigation scenarios), respectively,
    generally include socio-economic projections in
    addition to emission, concentration, and climate
    change information

46
AR5 Synthesis Report - 2014
  • The Synthesis Report discussed four areas
  • SPM 1. Observed Changes and their Causes
  • SPM 2. Future Climate Changes, Risks and Impacts
  • SPM 3. Future Pathways for Adaptation, Mitigation
    and Sustainable Development
  • SPM 4. Adaptation and Mitigation

47
Observed Changes and their Causes
  • Human influence on the climate system is clear,
    and recent anthropogenic emissions of greenhouse
    gases are the highest in history
  • Recent climate changes have had widespread
    impacts on human and natural systems

48
SPM 1.1Observed changes in the climate system
  • Warming of the climate system is unequivocal, and
    since the 1950s, many of the observed changes are
    unprecedented over decades to millennia
  • The atmosphere and ocean have warmed, the amounts
    of snow and ice have diminished, and sea level
    has risen

49
1880-2014 Temperature Anomalies
  • 2014 was the hottest year during this period

50
2014 Temperature Percentiles
51
SPM 1.2 Causes of climate change
  • Anthropogenic greenhouse gas emissions have
    increased since the pre-industrial era, driven
    largely by economic and population growth, and
    are now higher than ever
  • This has led to atmospheric concentrations of
    carbon dioxide, methane and nitrous oxide that
    are unprecedented in at least the last 800,000
    years
  • Their effects, together with those of other
    anthropogenic drivers, have been detected
    throughout the climate system and are extremely
    likely to have been the dominant cause of the
    observed warming since the mid-20th century

52
SPM 1.3 Impacts of climate change
  • In recent decades, changes in climate have caused
    impacts on natural and human systems on all
    continents and across the oceans
  • Impacts are due to observed climate change,
    irrespective of its cause, indicating the
    sensitivity of natural and human systems to
    changing climate

53
SPM 1.4 Extreme events
  • Changes in many extreme weather and climate
    events have been observed since about 1950
  • Some of these changes have been linked to human
    influences, including a decrease in cold
    temperature extremes, an increase in warm
    temperature extremes, an increase in extreme high
    sea levels and an increase in the number of heavy
    precipitation events in a number of regions

54
Future Climate Changes, Risks and Impacts
  • Continued emission of greenhouse gases will cause
    further warming and long-lasting changes in all
    components of the climate system, increasing the
    likelihood of severe, pervasive and irreversible
    impacts for people and ecosystems
  • Limiting climate change would require substantial
    and sustained reductions in greenhouse gas
    emissions which, together with adaptation, can
    limit climate change risks.

55
SPM 2.1 Key drivers of future climate
  • Cumulative emissions of CO2 largely determine
    global mean surface warming by the late 21st
    century and beyond
  • Projections of greenhouse gas emissions vary over
    a wide range, depending on both socioeconomic
    development and climate policy

56
SPM 2.2 Projected changes in the climate system
  • Surface temperature is projected to rise over the
    21st century under all assessed emission
    scenarios
  • It is very likely that heat waves will occur more
    often and last longer, and that extreme
    precipitation events will become more intense and
    frequent in many regions
  • The ocean will continue to warm and acidify, and
    global mean sea level to rise

57
SPM 2.3 Future risks and impacts caused by a
changing climate
  • Climate change will amplify existing risks and
    create new risks for natural and human systems
  • Risks are unevenly distributed and are generally
    greater for disadvantaged people and communities
    in countries at all levels of development

58
SPM 2.4 Climate change beyond 2100,
irreversibility and abrupt changes
  • Many aspects of climate change and associated
    impacts will continue for centuries, even if
    anthropogenic emissions of greenhouse gases are
    stopped
  • The risks of abrupt or irreversible changes
    increase as the magnitude of the warming increases

59
Future Pathways for Adaptation, Mitigation and
Sustainable Development
  • Adaptation and mitigation are complementary
    strategies for reducing and managing the risks of
    climate change
  • Substantial emissions reductions over the next
    few decades can reduce climate risks in the 21st
    century and beyond, increase prospects for
    effective adaptation, reduce the costs and
    challenges of mitigation in the longer term, and
    contribute to climate-resilient pathways for
    sustainable development.

60
SPM 3.1 Foundations of decision-making about
climate change
  • Effective decision making to limit climate change
    and its effects can be informed by a wide range
    of analytical approaches for evaluating expected
    risks and benefits, recognizing the importance of
    governance, ethical dimensions, equity, value
    judgments, economic assessments and diverse
    perceptions and responses to risk and uncertainty

61
SPM 3.2 Climate change risks reduced by
mitigation and adaptation
  • Without additional mitigation efforts beyond
    those in place today, and even with adaptation,
    warming by the end of the 21st century will lead
    to high to very high risk of severe, widespread,
    and irreversible impacts globally
  • Mitigation involves some level of co-benefits and
    of risks due to adverse side-effects, but these
    risks do not involve the same possibility of
    severe, widespread, and irreversible impacts as
    risks from climate change, increasing the
    benefits from near-term mitigation efforts.

62
SPM 3.3 Characteristics of adaptation pathways
  • Adaptation can reduce the risks of climate change
    impacts, but there are limits to its
    effectiveness, especially with greater magnitudes
    and rates of climate change
  • Taking a longer-term perspective, in the context
    of sustainable development, increases the
    likelihood that more immediate adaptation actions
    will also enhance future options and preparedness

63
SPM 3.4 Characteristics of mitigation pathways
  • There are multiple mitigation pathways that are
    likely to limit warming to below 2C relative to
    preindustrial levels.
  • These pathways would require substantial
    emissions reductions over the next few decades
    and near zero emissions of CO2 and other
    long-lived GHGs by the end of the century.
  • Implementing such reductions poses substantial
    technological, economic, social, and
    institutional challenges, which increase with
    delays in additional mitigation and if key
    technologies are not available.
  • Limiting warming to lower or higher levels
    involves similar challenges, but on different
    timescales

64
SPM 4. Adaptation and Mitigation
  • Many adaptation and mitigation options can help
    address climate change, but no single option is
    sufficient by itself
  • Effective implementation depends on policies and
    cooperation at all scales, and can be enhanced
    through integrated responses that link adaptation
    and mitigation with other societal objectives

65
SPM 4.1 Common enabling factors and constraints
for adaptation and mitigation responses
  • Adaptation and mitigation responses are
    underpinned by common enabling factors
  • These include effective institutions and
    governance, innovation and investments in
    environmentally sound technologies and
    infrastructure, sustainable livelihoods, and
    behavioral and lifestyle choices.

66
SPM 4.2 Response options for adaptation
  • Adaptation options exist in all sectors, but
    their context for implementation and potential to
    reduce climate-related risks differs across
    sectors and regions
  • Some adaptation responses involve significant
    co-benefits, synergies and trade-offs
  • Increasing climate change will increase
    challenges for many adaptation options

67
SPM 4.3 Response options for mitigation
  • Mitigation options are available in every major
    sector
  • Mitigation can be more cost-effective if using an
    integrated approach that combines measures to
    reduce energy use and the GHG intensity of
    end-use sectors, decarbonize energy supply,
    reduce net emissions and enhance carbon sinks in
    land-based sectors

68
SPM 4.4 Policy approaches for adaptation and
mitigation, technology and finance
  • Effective adaptation and mitigation responses
    will depend on policies and measures across
    multiple scales international, regional,
    national and sub-national
  • Policies across all scales supporting technology
    development, diffusion and transfer, as well as
    finance for responses to climate change, can
    complement and enhance the effectiveness of
    policies that directly promote adaptation and
    mitigation

69
SPM 4.5 Trade-offs, synergies and interactions
with sustainable development
  • Climate change is a threat to sustainable
    development
  • Nonetheless, there are many opportunities to link
    mitigation, adaptation and the pursuit of other
    societal objectives through
  • integrated responses (high confidence)
  • Successful implementation relies on relevant
    tools, suitable governance structures and
    enhanced capacity to respond (medium confidence)

70
What If?
  • What if the CO2 level keeps rising to well beyond
    twice the pre-industrial level along with a rise
    of other greenhouse gases, as must inevitably
    happen if we do not take strong action soon?
  • The results will certainly be worse
  • Under a "business as usual" scenario, recent
    calculations give even odds that global
    temperature will rise 5C or more by the end of
    the century
  • This will cause a radical reorganization and
    impoverishment of many of the ecosystems that
    sustain our civilization

71
What of the more distant future?
  • If emissions continue to rise for a century,
    whether because we fail to rein them in, or
    because we set off an unstoppable feedback loop
    in which the warming itself causes ever more
    greenhouse gases to be evaporated into the air,
    then the gases will reach a level that the Earth
    has not seen since tens of millions of years ago
  • The consequences will take several centuries to
    be fully realized, as the Earth settles into its
    new state
  • It is probable that, as in the distant geological
    eras with high CO2, sea levels will be many tens
    of meters higher and the average global
    temperature will soar far above the present
    value a planet grossly unlike the one to which
    the human species is adapted

72
Answering the Original Question
  • The foregoing discussion is intended as the
    answer to the question posed at the beginning
  • We are not just changing the climate, but we are
    engaged in a planet-wide, severe, alteration of
    the environment
  • For this reason, the title Global Environmental
    Change was deemed most appropriate

73
Bizarro
By Don Piraro
04-05-07
O8-08-03
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