Download Climate Change and Health Vulnerability Assessment

HSS4331 – International Health Theory
Feb 23, 2009 - Climate Change and Health
But before we begin….
Interview with African economist Dambisa Moyo:
http://www.nytimes.com/2009/02/22/magazine/22wwln-q4-t.html
Climate Change
Climate Change will affect population health everywhere
But there will be a particularly dramatic effect on
developing and poor nations.
From WHO website:
“Developing country populations, particularly in
Small Island States, arid and high mountain
zones, and in densely populated coastal areas, are
considered to be particularly vulnerable.”
From Stephen Lewis:
“Those places expected to be hardest hit by
Climate Change are precisely those places
currently being affected by HIV/AIDS, i.e.
Southern Africa.”
(not a precise quote)
What are some of the ways that Climate Change can affect health?
What are the mechanisms with which
Climate Change can affect population
health?
•Heat waves
•Floods and storms
•Water scarcity and quality
•Communicable diseases
•Air pollution
•Changing agriculture
•Migration
•Insecurity
•Economic effects
Heat Waves
-heat waves already kill hundreds, even thousands, every year
-in August 2003, 35000 people were killed in one week of intense heat in Europe
-exacerbated in urban environments
-less vegetative cover
-artificial surfaces are less cool
-greater local CO2 production
-frequency of heat waves are expected to increase
-according to WHO, heat deaths in California alone will double by 2100
-will also mean fewer cold waves globally, but this is only relevant in countries
with winter
-poor countries tend to be tropical, therefore more susceptible to heat waves
Floods and Storms
-the largest and fastest growing cities are on coasts
-construction patterns have led to less natural protection (eg erosion)
-poor quality housing makes people more vulnerable
-inadequate drainage in poor cities
-according to WHO, flooding will affect 200 million people by 2080
-in instances of flooding, it is always the poor who suffer most
-eg, Hurricane Katrina
-poor live in less secure structures
Asian tsunami anyone?
-poor live in more exposed areas
Places most susceptible to floods and storms?
-Nile delta in Egypt
-Ganges delta in Bangladesh
-small islands like the Maldives, the Marshall Islands and Tuvalu
Communicable
Diseases
-waterborne and vector borne diseases are strongly influenced by climate
-mosquitoes that carry dengue fever prefer high heat and humidity
-increasing global warming makes more habitats for mosquitoes
-increased population density means faster spread of such diseases
Water quality and scarcity
Because rivers are changing paths and rainfalls are
misscheduling, the predictability of the safety of drinking
water is uncertain.
•Already, 2 million deaths a year, mostly
among young children, are due to diarrhea,
directly caused by unsafe water.
•WHO estimates that today 2.4% of
diarrheal deaths are due to climate
change. (WHO uses very conservative
methods to reach these estimates.)
Air Pollution
-Atmospheric pollutants tend to be greater on hotter days (eg ozone)
-U.S. model predicts that by 2050, due to global warming, ozone-related
deaths will increased by 4.5% and there will be 60% more alert days
-exacerbated in emerging nations with lesser urban planning schemes (China)
Changing Agriculture
Agriculture is affected by temperature, precipitation and soil quality.
But in the long run, Climate Change affects agriculture by affecting:
•productivity
•agricultural practices (through changes of water use,
pesticides, etc)
•environmental effects (frequency and intensity of soil
drainage, etc)
•rural space (loss of land due to desertification)
•adaptation (change in biology of species)
Poor agriculture leads to
poor nutrition leads to
poor health
Changing Agriculture
Agriculture is affected by temperature, precipitation and soil quality
"southern Africa could lose
more than 30% of its main
crop, maize, by 2030. In
South Asia losses of many
regional staples, such as
rice, millet and maize could
top 10%". –Science (2008)
Poorest countries will be hit
hardest. Reduction in crop yield
in tropical and sub-tropical
regions caused by decreased
water and changed insect
behaviour. -IPCC (2001)
In Africa and Latin America many
rainfed crops are near their
maximum temperature tolerance,
so that yields are likely to fall
sharply for even small climate
changes; falls in agricultural
productivity of up to 30% over the
21st century are projected.
Marine life and the fishing
industry will also be severely
affected in some places. -IPCC
(2001)
Migration
There is a long established intersection between migration
and health:
-sudden stress of large numbers of people is ecologically bad
-environmental refugees must be fed, sheltered and cared for
-the world has a poor track record of caring for mass
migrants
-”Climate Refugees” (first used in 1988)
"The growing number of
disasters and conflicts linked to
future climate change will push
the numbers far higher unless
urgent action is taken. We
estimate that between now and
2050 a total of 1 billion people
will be displaced from their
homes.“ –Christian Aid (2007)
In 2005, half of Bhola
Island in Bangladesh
became permanently
flooded, leaving
500,000 people
homeless. They are
being called the
world's first Climate
Refugees. Washington Post
(2007)
1400 residents of Papua
New Guinea's Carteret
Islands are permanently
homeless because their
islands sank under rising
sea levels -Sydney Morning
Herald (2002)
Insecurity
War is bad for health. Need I explain why?
-high tension areas already exist with respect to water:
-South Asia (India, Pakistan, Bangladesh)
-Middle East (Lebanon, Israel, Iraq, Iran)
-freshwater needed for drinking and agriculture
-flowing water needed for industry, transportation and
clean energy
-with fossil fuels out of fashion, greater need for
hydroelectic power
-->dams
--> denial of flowing water downstream
-->conflict
Insecurity
War is bad for health. Need I explain why?
War has been known to be
triggered by climate.
Swings in temperature
were correlated with times
of war in Eastern China
between 1000 and 1911. Human Ecology (2007)
"Water at large is
the central [global
warming] problem
for the USA" Princeton University
Israel and Lebanon
almost went to war in
2003 over fresh water
from the Hasbani
river.
Global warming
constitutes a security
threat to the USA, as
there will be wars based
on diminishing fresh
water supplies, refugees,
and higher rates of
famine and disease -The
Pentagon (2007)
Less money means less public health.
Economic Effects
Coral bleaching can
lead to collapse of the
world’s fisheries in a
matter of decades –Am
J Prev Med (2008)
Case study: Washington State(Dept of Ecology, 2008):
•Direct costs of fighting wildfires > $75 million per year by
the 2020s.
•Water conservation costs = $16 million by 2040
•Public health costs
•Tourism and recreation losses
•Hydropower revenues down by $166 million by 2020
•Water price increases in some basins = $680,000 per
million gallons per day.
•Dairy revenue loss = $6 million per year by the 2040s
•Crop losses = $66 million
•Shoreline protection = $50 million
•Flooding costs
•Cumulative economic effects (As one industry declines,
another may follow.)
Aside: Psychosocial effects
Health Canada 2007 report “Climate Change and Health
Vulnerability Assessment:
The Public Health Agency of Canada is undertaking a study on
the projected mental health effects of environmental stressors
resulting from Climate Change.
Synergy of Climate Effects
Floods can cause cholera
and diarrhea, damage
infrastructure for years, and
can contribute to a pathway
making oral vaccines less
effective.
Drought exacerbates
malnutrition, causes
populations to migrate,
where they are
exposed o new
patterns of vectorborne diseases.
Climate change causes urban
heat waves, causing
increased use of air
conditioners, increasing
demand for electricity, leading
to further use of coal plants...
Health Canada breaks down the climate change – health relationship like so:
Temperature-related morbidity and mortality:
-cold and health related illnesses
-respiratory and CV illnesses
-increased occupational health risks
Health effects of extreme weather events:
-damaged public health infrastructure
-injuries and illnesses
-social and mental stress
-occupational health hazards
-population displacement
Air pollution related illnesses:
-changed exposure to outdoor allergens
-asthma, etc
-CV diseases (heart attacks, strokes, etc)
-cancer
Water and food borne contamination:
-diarrhea
-toxic algal blooms
Vector and zoonotic diseases:
-changed patterns of diseases caused by insects, bacteria, etc
Exposure to UV rays
-skin damage and cancer
-cataracts
-disturbed immune function
Vulnerable populations
-seniors
-kids
-chronically ill people
-poor people
-Northern residents
-disabled people
-people “living off the land”
Socioeconomic impacts:
-loss of income and productivity
-social disruption
-diminished quality of life
-increased costs to health care
-health effects of mitigating technologies (eg, air conditioners)
In 2006, the WHO did a study of project health impacts on
Oceania for the year 2050, based on expected changes in
global climate.
VOLUME 114
| NUMBER 12 | December 2006 • Environmental Health
Perspectives
In addition, they computed for Sub-Saharan Africa, for the year 2030:
-mortality from flooding would be almost
twice as likely
-increase in malaria
-increase in malnutrition due to
destruction of crops and change in
harvest season
-increase in diarrhea due to reduced
water control
Sobering statistic:
“Measurement of health effects from climate
change can only be very approximate.
Nevertheless, a WHO quantitative assessment,
taking into account only a subset of the possible
health impacts, concluded that the effects of the
climate change that has occurred since the mid1970s may have caused over 150,000 deaths in
2000. It also concluded that these impacts are
likely to increase in the future.”
WHO's official position:
WHO considers that rapid climate change poses
substantial risks to human health, particularly
among the poorest populations. The organization
therefore supports actions to reduce human
influence on the global climate.
Important issues:
-climate change denial slows down investment in projects to address
these issues
-climate change affects different regions in very different ways
-poor countries cannot afford to do basic risk assessment
-global rush to cities and to coasts is ever accelerating
-effects on food production are impossible to predict (though Africa is
thought to be most vulnerable)
-mass migration (environmental refugees) highly likely
-conflict resulting from both mass migration and competition for resources
is also likely
-a global issue requires a global solution
Another word about water...
-Case study: China
-In China, by 2030, population will be 1.6 billion and water
demand will equal 100% of China's supply
-70% of China's lakes and 5 of its rivers are too polluted for
human use
-China's glaciers are shrinking 7% each year, due to global
warming
->this threatens the source of these rivers: Yangtze, Yellow,
Brahmaputra, Mekong and Salween, which feed 500 million
people downstream
-China uses 7-15 times more water to produce a unit of GDP
than do more developed nations
->therefore some of this is preventable!
Water Availability Per Capita, 2007
www.earthtrends.wri.org
A word about scientific uncertainty....
the Canadian Environmental Protection Act (1999) states:
“...where there are threats of serious or irreversible damage, lack of full
scientific certainty shall not be used as a reason for postponing costeffective measures to prevent environmental degradation.”
So what is being done?
WHO:
-continue what they've always done, addressing
infectious disease, malnutrition, etc
-workshops to “raise awareness” of climate change in
developing world
-advocate for green infrastructure, such as public
transportation
-advocate for improved urban infrastructure, such as
better drainage
-proposed creation of “global climate change fund”
More things that need to be done:
-improved global disease surveillance
-improved response systems to disease outbreaks
-better global risk assessment, to identify vulnerable areas and
possible interventions
-international bodies for managing shared resources, like water
-research, research, research
--> how will crops behave as climate changes?
--> how will vector populations (insects, rodents) behave?
--> where will freshwater be most needed?
-->etc