Australian media is giving good coverage to the IPCC report - but the NZ media, to its eternal shame, is not.
Climate
change and health: IPCC reports emerging risks, emerging consensus
The
Intergovernmental Panel on Climate Change’s (IPCC) Impacts volume
of the Fifth
Assessment Report will
be released today. Here, three contributors to the health chapter
explain the ideas and evidence behind the report.
31
March, 2014
The
consequences of human-driven global climate change as this century
progresses will be wide-ranging. Yet public discussion has focused
narrowly on a largely spurious debate about the basic science and on
the risks to property, iconic species and ecosystems, jobs, the GDP
and the economics of taking action versus taking our chances.
Missing
from the discussion is the threat climate change poses to Earth’s
life-support system – from declines in regional food yields,
freshwater shortage, damage to settlements from extreme weather
events and loss of habitable, especially coastal, land. The list goes
on: changes in infectious disease patterns and the mental health
consequences of trauma, loss, displacement and resource conflict.
In
short, human-driven climate change poses a great threat,
unprecedented in type and scale, to well-being, health and perhaps
even to human survival.
Extreme
weather events have contributed to a rise in global food prices.
'Palm Trees, Wind and Ocean' by Brooke/Flickr, CC BY-NC-SA
The
human health chapter in the second (“Impacts”) volume of the
IPCC’s Fifth Assessment Report concludes that the scientific
evidence of many current and future risks to health has strengthened
in recent years. The chapter, as in all IPCC reports, reviews all
existing scientific evidence and is subject to external peer-review.
During
at least the next few decades, the chapter states, climate change
will mainly affect human health, disease and death by exacerbating
pre-existing health problems. The largest impacts will occur in
poorer and vulnerable populations and communities where
climate-sensitive illnesses such as under-nutrition and diarrhoeal
disease are already high – thus widening further the world’s
health disparities.
Currently,
the worldwide burden of ill-health clearly attributable to climate
change is relatively small compared with other major blights on
health such as from poverty, poor sanitation and exposure to tobacco.
Even
so, in this early stage of human-driven climate change researchers in
many countries have reported that rising temperatures and changing
rainfall patterns have, variously, increased heat-related illnesses
and deaths, altered the distribution of some water-borne infectious
diseases and the insect transmitters (vectors) of some diseases (such
as malaria), and have reduced food yields in some already
food-insecure populations.
Less
certainly, extreme weather events, influenced in part by climate
change, are likely to have contributed to the recent rise in global
food prices.
Climate
change may render some regions uninhabitable. Shutterstock
The
chapter discusses three impact categories in particular:
- under-nutrition and impaired child development due to reduced food yields
- injuries, hospitalisations and deaths due to intense heat waves, fires and other weather disasters and
- shifts in the seasonal duration and spatial range of infectious diseases.
There
is also mounting evidence of the adverse health consequences of
workplace exposure to heat extremes, including reduced work capacity
and productivity.
Looking
ahead to 2100, for which some modelled scenarios now project an
average global warming of 4 degrees Celsius, the report foresees that
in such conditions people won’t be able to cope, let alone work
productively, in the hottest parts of the year. And that’s assuming
social and economic institutions and processes are still intact. Some
regions may become uninhabitable.
Impacts
on mental health could be similarly extreme, further limiting our
collective capacity to cope, recover and adapt.
Overall,
while limited health gains from climate change may occur in some
regions, the health chapter concludes from the evidence that harmful
impacts will greatly outweigh benefits. The impacts of climate change
will also undermine hard-won gains achieved through social
development programs, impeding progress in the world’s poorest
countries.
The
world community has dithered for two decades over climate change
since it rose to prominence during the 1992 Earth Summit. As valuable
time to reduce the risks (mitigation) has been squandered, the need
to also focus on managing risk (adaptation) has increased. But
excessive reliance on adaptation carries its own risks – including
fooling ourselves that we don’t need immediate and aggressive
mitigation.
Public
health programs can help manage the effects of climate change.
Department of Foreign Affairs and Trade, CC BY
The
health chapter concludes that the most immediate effective way to
manage health risks is through programs that introduce or improve
basic public health measures. It also notes the need to boost human
rights-based access to family planning.
As
climate change proceeds, additional climate-specific measures (such
as enhanced surveillance, early warning systems and climate-proofed
building design) will be needed to protect population health, even in
high-income settings. Recent extreme events such as the severe heat
waves and fires in Australia in 2009-2014 and in Russia in 2010
underscore this need.
The
chapter offers some cheer in stressing that the near-term and
relatively localised health “co-benefits” from reducing
greenhouse emissions (mitigation) could be very large. Reducing
emissions of methane and black carbon, for example, may avoid more
than two million deaths per year.
- Other mitigation actions likely to improve physical health, social connectedness and mental health include:
- encouraging communities to be more active via improved public transport and reduced car reliance
- reducing exposures to temperature extremes with well-insulated energy-efficient housing and
- promoting healthier diets through the transformation of food production and processing systems.
Impacts
of climate change on mental health limit our capacity to cope,
recover and adapt. Tim Caynes, CC BY-NC
In
economic terms, the IPCC chapter judges that the health co-benefits
from reducing emissions would be extremely cost-beneficial. They
would, for example, be one thousand times greater than the economic
co-benefits to agricultural yields from reduced exposures to
short-lived, crop-damaging, airborne climate pollutants.
Overall,
the up-front costs of reducing emissions could be substantially
offset by early and extremely large health (and other) benefits.
Of
course, none of this matters if human well-being, health and survival
mean little to us. In that case we can emit all we like, then suffer,
dwindle or even die out as a species and leave this planet to recover
and thrive without us. One way or another we will then emit less.
We
have a closing window of time in which to do something about global
climate change.
Again, "adaptation" to climate change which the IPCC sees progressing in a linear manner. Better not mention those pesky positive feedbackss!
IPCC:
Australia and New Zealand face greater fire and flood risk, damage to
coral reefs
Australia’s coral reefs and mountain-top ecosystems are set to suffer from climate change, according to the Intergovernmental Panel on Climate Change’s latest summary of the research
31
March, 2014
The
threats to these ecosystems are among a host of climate risks posed
to Australia and New Zealand, which also includes increased danger
from extreme weather events and bushfires, as well as the threat from
rising seas and drying river systems.
Many
of these risk have become even more evident since they were discussed
in the previous 2007 IPCC report, and will almost certainly intensify
even if remedial efforts are undertaken.
This
report – the second volume of the Intergovernmental Panel on
Climate Change (IPCC) Fifth Assessment Report – deals with the
impacts of climate change, our vulnerabilities to it, and how we
might adapt. It contains a dedicated chapter on Australia and New
Zealand, prepared by eight lead authors coordinated by me and Andy
Reisinger, with assistance from 37 corresponding authors.
Its
message should be cause for concern but, as we shall see, not
necessarily despair.
Key
climate risks for Australia and New Zealand in the new IPCC climate
impacts and adaptation summary. IPCC , CC BY-NC-ND
Corals
set to suffer
Significant
impacts, including bleaching, coral death and a range of coral
diseases, are leading to changes in the structure and species makeup
of corals on both the Great Barrier Reef and Western Australia’s
Ningaloo Reef.
These
natural ecosystems have little ability to adapt and, other than
reducing other detrimental effects such as nutrient run-off and
over-exploitation, there seems little we can do about it in the short
term.
The
same is true of mountain-top ecosystems in Australia’s tropical and
alpine zones. Mammals and birds, as well as whole sets of other
species endemic to the tops of mountains, simply have nowhere to go.
Floods,
heatwaves and fires on the rise
Extreme
events such as floods, heatwaves and bushfires are all set to
increase in both frequency and intensity. Recent events underscore
our vulnerability to weather extremes.
Without
serious mitigation, increases of up to 200% by 2090 for extreme
rainfall events for some regions of Australia are projected in some
models. For New Zealand the projections are for an 8% increase for
each 1°C increase in temperature.
Hot
days in Melbourne (over 35°C maximum) are projected to increase by
20-40% by 2030, 30-90% by 2070, and by 70-190% by 2070.
In
New Zealand, spring and autumn frost-free land is projected to at
least triple by 2080 and up to 60 more hot days (over 25°C maximum)
are projected for northern areas by 2090.
Depending
on the model used, days with a very high and extreme fire danger
index will increase in Australia by 2-30% by 2020, and by 5-100% by
2050. For New Zealand, extreme fire days are projected to increase
from around 0 to 400% by 2040), and by 0 to 700% by 2090, again
depending on the climate model used.
The
number of fire danger days is set to rise in Australia and New
Zealand. AAP
But,
unlike for coral reefs, we may be able to adapt to these problems, at
least under the less extreme climate projections: that is, those that
envisage gradually declining carbon emissions globally.
Both
Australia and New Zealand are set to suffer more major flooding
events – and as a result, simply bunkering down and hoping for the
best may not be the most prudent course of action. So-called
“transformational adaptation” may be the better long-term
solution, with planned retreat from most vulnerable areas.
Similarly,
sustained periods of extreme heat bring significant health risks, and
the devastating impacts of bushfires on human life, property and
ecosystems are all too well known. The Black Saturday bushfires in
2009 caused 173 deaths and destroyed A$4 billion worth of
infrastructure. A further 374 deaths are estimated to have been
caused by the extreme heatwave conditions in southeastern Australia
in 2009.
Reduced
rainfall in parts of southern Australia will impose greater stresses
on water availability and consumption.
All
of these risks, however, can be reduced to some extent by changes in
management regimes. The IPCC report draws attention clearly to known
impacts and current projections and are intended to provide the
strongest possible scientific basis for governments to construct
future policies.
Sea
levels and droughts: an uncertain future
There
are two more key threats, the severity of which will depend on how
the various possible climate scenarios play out in the future.
If
sea levels rise by a metre by the end of the century (within the
range of model projections), the consequences for those who live in
coastal towns and cities would be immense. That’s a particular
problem for Australia and New Zealand, where the majority of the
population is clustered in coastal areas.
Similarly,
the drier scenarios projected by some models could affect Australia’s
food productivity in its major food-producing regions: the
Murray-Darling Basin, the far southwest and the far southeast. Our
heavy dependence on these regions as the nation’s food bowls means
that these risks, even though at the lower ends of the probability
spectra, must be taken seriously. These less likely but more extreme
scenarios project declines in annual rainfall of up to 30% for 2070
in South Australia with some larger declines seasonally.
Local
steps but a lack of overall action
Some
local governments are taking concrete steps to manage these various
risks, but overall implementation is patchy. The preferred options
have tended to be “incremental”: gradual adjustments that should
allow us to maintain our current lifestyles. Examples include raising
levee banks to cut flood risk; increasing fire-fighting resources and
bushfire education; and the introduction of water-conservation
programs.
These
actions are all both necessary and desirable, but without strong
action to limit future climate change – the subject of the IPCC’s
next report in April – they will become increasingly inefficient,
expensive and even futile in the long term.
The
alternative is the sort of transformational adaptation mentioned
earlier, which would involve taking more radical measures to address
the threats. This might involve planned retreats from low-lying
coastal zones or high-risk fire areas, or introducing new crop
strains or shifting farming to new areas.
Some
authorities and individuals have taken tentative steps down these
paths, but it is clearly a huge challenge to coordinate such
large-scale shifts. At least one local council on Australia’s east
coast has attempted to promote planned retreat policies, only to have
these overturned upon legal challenge.
Meeting
the climate challenge
There
is no doubt about the main threats that face Australasia, although
there is obviously still some uncertainty about the finer details. In
the seven years since the 2007 IPCC Assessment Report, we have
learned more about potential climate impacts on biodiversity, human
health, agriculture and forestry, rural communities and urban
infrastructure.
During
that time our knowledge about possible ways to adapt to these various
threats has grown even faster. We might feel helpless in the face of
the climate challenge, but really we’re not – although bringing
action to bear will involve a big collective effort.
Without
substantial adaptation the impacts will only intensify across all
sectors of society and the environment. But as the report notes,
there are many constraints on the implementation of such adaptation
measures. These include the need for consistency and reduced
uncertainty in projections, as well as more clarity on local impacts.
There
is also a lack of guidance on principles and priorities for action,
as well as the responsibilities of different levels of government,
from the United Nations right down to local councils. There are also
widely differing attitudes among the community to both climate change
risk and the value of particular objects and places. These remain as
challenges for the future.
IPCC
reports give a wealth of information to politicians, but it is not
their job to recommend policies. That remains the purview of
politicians and the public - although everybody has a stake in
meeting this challenge.
This
article is based on the Executive Summary of the Australasia Chapter
of the IPCC’s Working Group II report: Climate
Change 2014: Impacts, Adaptation and Vulnerability.
The chapter’s Executive Summary was prepared by Andy Reisinger,
Roger Kitching, Francis Chiew, Lesley
Hughes,
Paul Newton, Andrew Tait, Sandra Schuster and Penny
Whetton
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