limate change is one of the most complex issues facing us today.
It involves many
dimensions – science, economics, society, politics and moral and ethical questions –
and is a global problem, felt on local scales, that will be around for decades and
centuries to come. Carbon dioxide, the heat-trapping greenhouse gas that has
driven recent global warming, lingers in the atmosphere for hundreds of years, and
the planet (especially the oceans) takes a while to respond to warming. So even if
we stopped emitting all greenhouse gases today, global warming and climate
change will continue to affect future generations. In this way, humanity is
“committed” to some level of climate change.
How much climate change? That will be determined by how our emissions continue
and exactly how our climate system responds to those emissions. Despite
increasing awareness of climate change, our emissions of greenhouse gases
continue on a relentless rise. In 2013, the daily level of carbon dioxide in the
atmosphere surpassed 400 parts per million for the first time in human history. The
last time levels were that high was about three to five million years ago, during the
Pliocene Epoch.
Because we are already committed to some level of climate change, responding to
climate change involves a two-pronged approach:
1. Reducing emissions of and stabilizing the levels of heat-trapping greenhouse
gases in the atmosphere (“mitigation”);
2. Adapting to the climate change already in the pipeline (“adaptation”).
Mitigation and Adaptation
Credit: trekandshoot/Shutterstock.com
Mitigation – reducing climate change – involves reducing the flow of heat-
trapping greenhouse gases into the atmosphere, either by reducing sources of
these gases (for example, the burning of fossil fuels for electricity, heat or transport)
or enhancing the “sinks” that accumulate and store these gases (such as the
oceans, forests and soil). The goal of mitigation is to avoid significant human
interference with the climate system, and “stabilize greenhouse gas levels in a
timeframe sufficient to allow ecosystems to adapt naturally to climate change,
ensure that food production is not threatened and to enable economic development
to proceed in a sustainable manner” (from the 2014 report on Mitigation of Climate
Change from the United Nations Intergovernmental Panel on Climate
Adaptation – adapting to life in a changing climate – involves adjusting to
actual or expected future climate. The goal is to reduce our vulnerability to the
harmful effects of climate change (like sea-level encroachment, more intense
extreme weather events or food insecurity). It also encompasses making the most of
any potential beneficial opportunities associated with climate change (for example,
longer growing seasons or increased yields in some regions).
About mitigation and adaptation
Any comprehensive long-term strategy for minimizing the risks associated with climate change
requires the combination of planned adaptation to and mitigation of climate change.
Adaptation
Adaptation refers to initiatives and measures to reduce the vulnerability of natural and human
systems to actual or expected effects of climate change. They aim at minimizing potential impacts of
climate change, and to reduce, with the least cost, the adverse effects on health.
In the context of health protection, adaptation encompasses all actions that protect populations from
the health impacts of climate change. For adaptation to be effective, it is necessary to understand
the current and projected climate change impacts and their implications for health, and then to
develop and implement a range of responses to ensure an optimal level of adaptation.
Mitigation
Mitigation refers to actions that limit the extent and rate of climate change by constraining the
emissions of greenhouse gases or enhancing their sinks.
Mitigation entails several public health benefits, for instance increased physical activity due to the
promotion of cycling and walking, and pollution reduction associated with increased non-motorized
transportation.
Efforts to integrate health in mitigation and adaptation policies are best supported by adequate
accountability and monitoring of the effectiveness of the interventions, as well as their costs, benefits
and distributional impacts.
Public health impact of strategies to reduce greenhouse gas emissions
Lancet series on energy
Climate change and health: a tool to estimate health and adaptation costs (2013)WHO
limate change adaptation (CCA) is a response to global warming (also known as "climate
change").[1]
SDG13 targets to strengthen countries' resilience and adaptive capacities to climate-related issues.
[2]
The Intergovernmental Panel on Climate Change (IPCC) defines adaptation as: 'the process of
adjustment to actual or expected climate and its effects. In human systems, adaptation seeks to
moderate or avoid harm or exploit beneficial opportunities. In some natural systems, human
intervention may facilitate adjustment to expected climate and its effects'. [3] This adjustment includes
many areas such as infrastructure,[4] agriculture[5] and education.
Even if emissions are stabilized relatively soon, global warming and its effects will last many years
due to the delay times caused by past global warming, and adaptation would be necessary to the
resulting changes in climate.[6] If all greenhouse gas emissions were to stop today, the Earth’s
average surface temperature would climb another 0.6 degrees over the next decades before
temperatures stopped rising.[7]
Adaptation actions can be considered as either incremental adaptation (actions where the central
aim is to maintain the essence and integrity of a system) or transformational adaptation (actions that
change the fundamental attributes of a system in response to climate change and its impacts). [8]
The need for adaptation varies from place to place, depending on the sensitivity and vulnerability to
environmental impacts.[9][10] Adaptation is especially important in developing countries since those
countries are bearing the brunt of the effects of global warming. [11] Human adaptive capacity is
unevenly distributed across different regions and populations, and developing countries generally
have less capacity to adapt.[12]
Adaptive capacity is closely linked to social and economic development.[13] The economic costs of
adaptation to climate change are likely to cost billions of dollars annually for the next several
decades, though the exact amount of money needed is unknown. [14]
The adaptation challenge grows with the magnitude and the rate of climate change. Even the most
effective climate change mitigation[15] through reduction of greenhouse gas (GHG) emissions or
enhanced removal of these gases from the atmosphere (through carbon sinks)[16] would not prevent
further climate change impacts, making the need for adaptation unavoidable. [17] However, climate
change may be too much for some natural ecosystems, such as coral reefs, to be able to adapt.
[18]
Others are concerned that climate adaptation programs might interfere with the existing
development programs and thus lead to unintended consequences for vulnerable groups.[19] The
economic and social costs of unmitigated climate change would be very high. [20]
