Serious consequences of climate changeUpdated 01/20/2014, published online 11/29/2010
The melting of ice floes, the disappearance of some species, epidemics and economic recession – climate change could have serious consequences. However, individuals and policymakers are becoming more aware of these issues, which is encouraging.
A disrupted climate
Empirically, the public is becoming aware of the climate changes underway. For example, everyone remembers the exceptional heat wave in 2003.
For scientists, indicators of climate change are as follows:
• An increase in the frequency of heat waves;
• A reduction in the surface area and thickness of glaciers (retreat);
• The melting of ice floes;
• The loss of mass of polar ice sheets in the Antarctic and Greenland;
• Increased average ocean levels;
• Disruptions to the water cycle, which may lead to very heavy rainfall (flooding) or prolonged droughts;
• Changes in vegetation (flowering dates, harvest times, etc.);
• Migrations of animal species (e.g. insects).
mpirically, the public is becoming aware of the climate changes underway. For example, everyone remembers the exceptional heat wave in 2003.
Entire populations affected
Climate change has effects on public health that are difficult to quantify. Many other factors come into play (organization of the health system, state of development, etc.).
Nevertheless, public health is affected by climate:
• Heat waves have consequences on particularly vulnerable populations (older people, newborns or persons with respiratory problems, particularly asthma).
• Air quality is altered, which also affects vulnerable people and those suffering from cardio-respiratory problems.
• Changes in pollen production are one of the reasons why allergies are on the rise in most countries.
• Movements of insects carrying epidemics (malaria, dengue) can lead to the extension of the areas at risk of these epidemics.
Climate changes also affect farm production and fishing resources, which in turn have consequences on people's food supply. Finally, extreme events (tsunamis, floods) can come with epidemics such as cholera.
Adaptation processes are being drafted to combat these risks. For example, in France, the Haut Conseil de la Santé Publique (Public Health Council) has been tasked with setting up a think-tank on adapting to climate change.
A troubled economy
It is very difficult to estimate the economic impact of climate change. According to economists, the cost varies from 2 to 50 euro per ton of carbon emitted. Some experts predict even higher1.
According to British economist Nicholas Stern2, the cost of climate change will be considerable in the coming decades. It could lead to a major recession (of some 20% of global GDP) – whereas combating climate change would cost 1% of global GDP. The debate on the value of these figures and on the assumptions underlying them is intense, but this argument aims to convince economic stakeholders and decision-makers of the necessity to act.
• Decide on strict guidelines to remove carbon from developed economies and emerging countries alike;
Becoming aware of the reality of climate change and its consequences is the first step in implementing solutions, from changes in everyday behavior to international policies.
Today we know that the increase in greenhouse gas emissions cannot be reduced fast enough to prevent a temperature rise. It is now necessary to implement adaptation strategies across the board to limit and counter the impacts of climate change.
Furthermore, taking action to control greenhouse gas emissions (and anticipate the consequences of climate change) may have other positive consequences, on employment, air quality and quality of life.
Adaptation across the board
While emissions reduction primarily consists of international action, adaptation concerns a vast number of mostly local actions affecting all sectors. These include managing water, agriculture, infrastructures and human settlements, transport, healthcare, energy and transport systems3. By way of illustration, a health risk management program during severe heat waves could be considered as part of an adaptation strategy.
Take France's "Plan national d'adaptation au changement climatique4 " (National climate change adaptation program) which takes effect during the 2011-2015 period. It outlines a catalog of 80 initiatives supported by 230 measures and recommendations within several fields (especially biodiversity, health, and agriculture). This plan represents a €171 M budget, adding to the €391 M already allocated for "Investissements d'Avenir" (Investments for the Future program).
• Reducing water consumption in all sectors (-20% by 2020);
Implementing this system is a first in Europe. An assessment report will be produced at the half-way point and presented at the end of 2013. A final assessment will be made in 2015.