The Health Practitioner's Guide to Climate Change

Diagnosis and Cure

Jenny Griffiths, Mala Rao, Fiona Adshead, Allison Thorpe

• Publisher: Routledge
• Year: 2009
• ISBN:
  9781136573446
• Edition: 1
• Topic: Medicine
• Subtopic: Public Health, Administration & Care

Highly commended in the Public Health category, BMA Medical Awards 2010

There are enormous health benefits from tackling climate change. This is the first book to set out what health practitioners can do to prevent the worst impacts of climate change, to make health services sustainable, and to design healthy, sustainable communities.

The book:
- provides an introduction for health practitioners and students to climate change and its current and future health impacts
- describes the relationship between health and the environment
- gives facts and figures on greenhouse gas emissions
- sets out the huge benefits to health of acting on climate change
- explains what health practitioners can do - at home, at work and in their organizations, and
- shows how you can support action in communities, nationally and globally.

Essential reading for:
- health professionals, local government, built environment professionals
- students across all sectors of health, medicine and public administration
- community and voluntary sector, NGOs
- the business community involved in private healthcare.

The Health Practitioner's Guide to Climate Change is written by an authoritative group of authors from key organisations in the field, including the Met Office, the Faculty of Public Health, Natural England, the London School of Hygiene and Tropical Medicine, the Climate and Health Council, the NHS Sustainable Development Unit, the Health Protection Agency, the University of the West of England, Sustrans and the National Social Marketing Centre.

Sponsored by The National Heart Forum and the National Social Marketing Centre.

Foreword by Dr. R.K. Pachauri, Director General, The Energy and Resources Institute (TERI) and Chairman, Intergovernmental Panel on Climate Change (IPCC)

Part 1

Information

1	Greenhouse Gas Emissions: The Hard Facts

Felicity Liggins

Climate change is the most severe problem that we are facing today – more serious even than the threat of terrorism.

Sir David King

(former Chief Scientific Advisor to the UK Government), 2004

Summary

Climate change is a natural phenomenon, but humankind has drastically altered the process. When we use computers to model only the natural influences on the climate, we cannot explain the rapid rise in global temperatures we have seen during the 20th century. It is only when we include the influence of our emissions of greenhouse gases into the atmosphere over the last 150 years that we can replicate the temperature rises seen in recent decades. To help to avoid unacceptably dangerous climate change in the future, many countries and regions have set targets for reducing their greenhouse gas emissions. The UK Government has set a target of an 80 per cent cut in emissions on 1990 levels by 2050 as part of the Climate Change Act of 2008. Various national and international organizations have also set themselves targets to reduce the impact they have on the climate, with the National Health Service in England aiming to reduce its greenhouse gas emissions by at least 80 per cent by 2050. This chapter concludes with some responses to frequently asked questions about climate change.

Key Terms

Carbon sink: A reservoir that removes carbon dioxide from the atmosphere and provides storage over a period of time; the reservoir can be a natural sink, for example trees and oceans absorb vast quantities of carbon dioxide, or a man-made one, such as carbon capture and storage schemes.

Climate: The average weather, encompassing natural variability and extremes.

Greenhouse gas: A gas that contributes to trapping heat in the atmosphere, warming the Earth, including carbon dioxide, methane and water vapour; they are both naturally occurring and also released into the atmosphere by humankind.

Global warming: The rise in global temperature observed during the 20th century and projected to continue into the future, caused by human beings’ increased emissions of greenhouse gases.

Climate change: The changes in the observed and projected climate around the world; a natural phenomenon altered due to human beings’ activities; a more comprehensive term than global warming as it also includes changes to rainfall, ocean and atmosphere circulation patterns and sea level.

Adaptation: Taking action to minimize the current and expected impacts of climate change.

Mitigation: Taking action to reduce greenhouse gas emissions and enhancing natural and artificial processes that remove greenhouse gases from the atmosphere.

Global warming potential (GWP): A term indicating how much a greenhouse gas contributes to global warming when compared to the same amount of carbon dioxide over a set period of time (often 100 years); for example, the GWP of methane over 100 years is 23, meaning that 23 tonnes of CO₂ would need to be emitted to cause the same effect as 1 tonne of methane.

Equivalent carbon dioxide (CO₂e) emissions: A measure used to compare how much CO₂ would need to be emitted to cause the same effects on the climate as a particular emission of a greenhouse gas or a range of greenhouse gases, over a set period of time; it is calculated by multiplying the emissions of the greenhouse gas(es) by their appropriate global warming potentials, and is often measured in million tonnes of CO₂e (MtCO₂e).

Equivalent carbon dioxide (CO₂e) concentration: A measure used to compare what concentration of CO₂ would be needed to cause the same radiative forcing as a particular concentration of a greenhouse gas or a range of greenhouse gases; this is typically used to combine the effects of carbon dioxide, methane and nitrous oxide, and is measured in parts per million by volume (ppmv).

IPCC AR4: Intergovernmental Panel on Climate Change Assessment Report 4; the IPCC is a scientific intergovernmental body set up by the World Meteorological Organization and the United Nations Environment Programme to provide decision-makers and others with an objective source of information about climate change.

Radiative forcing: the effect greenhouse gases and other pollutants, either individually or combined, have on the net amount of incoming and outgoing radiation received at the tropopause, the atmospheric boundary below which all weather occurs. A net positive change in radiative forcing usually results in more warming of the atmosphere, a net negative change results in cooling.

UKCIP: United Kingdom Climate Impacts Programme; designed to provide organizations with the most up-to-date information on the nature of the climate in the future in the UK and help them adapt to its effects.

UNFCCC: United Nations Framework Convention on Climate Change; an international treaty, signed by 192 countries, concerning what might be done to mitigate and adapt to climate change.

Kyoto Protocol: An addition to the UNFCCC, providing legally binding measures to reduce greenhouse gas emissions; the gases or groups of gases covered by the Kyoto Protocol are carbon dioxide, methane, nitrous oxide, sulphur hexafluoride, hydrofluorocarbons and perfluorocarbons; by December 2008 it had been ratified by 183 parties.

How is Our Climate Changing and are we to Blame?

The Earth’s climate has always varied over time. Until the 20th century, these changes were a result of natural processes. By studying lots of different resources, such as ice cores and ocean sediments, scientists can reconstruct the global climate back through the geological ages. Global average temperatures have fluctuated by as much as 9°C, with ice ages coming and going. Sea levels 86 million years ago were over 200 metres higher than they are today, whereas at the end of the last ice age 18,000 years ago they were about 120 metres lower.

Since the middle of the 19th century, increasingly detailed weather and climate measurements have been made around the world. Researchers have uncovered dramatic changes in climate since the Industrial Revolution that cannot be attributed to natural causes. During the 20th century, average global nearsurface temperatures rose by over 0.7°C (IPCC, 2007). Figure 1.1 shows how temperatures have varied from 1850 to the present day. Sea levels have also risen, putting communities, large and small, at ever greater risk from coastal flooding and coastal erosion. Severe weather events such as heatwaves, floods and droughts have occurred more frequently.

Figure 1.1 Graph showing the increase in annual average surface temperature since 1850 (with respect to 1961–1990 average surface temperature)

Source: © Met Office (2008)

Over recent years, researchers from around the world have modelled the oceans and atmosphere to see how our climate has behaved in the past, how it works today and how it might evolve in the future. A number of natural processes influence our climate. Variations in the way the Earth orbits around the sun and also the sun’s output can cause changes in how much heat, in the form of solar radiation, we receive over cycles ranging in length from just decades to hundreds of thousands of years. Additionally, volcanic eruptions releasing huge amounts of dust and gas into the atmosphere can cause global temperatures to drop for several years as more of the sun’s energy is reflected back out into space.

When scientists model how the climate has changed during recent decades, using just these natural phenomena, they cannot account for the rapid rise in global mean temperatures that has been observed in the last few decades, as demonstrated in Figure 1.2. The black line here represents the observed global temperatures; the grey shaded area is the range of results from a climate model. The consensus of scientists, as summarized in the IPCC AR4 (2007), is that natural causes alone are insufficient to explain many of the observed changes in climate over the last 100 years or so. It is the impact of human activities on the atmosphere and oceans, superimposed on natural variations, which has led to many of the observed changes, particularly the rising temperatures, as shown in Figure 1.3 where the observations and modelled results align.

Figure 1.2 Graph showing how observed global temperature changes differ when compared to those modelled using only natural processes

Source: Stott et al (2000)

Figure 1.3 Graph showing how observed global temperature changes correspond to those modelled using natural and human-induced processes

Source: Stott et al (2000)

How do we Contribute to Climate Change?

Without greenhouse gases like carbon dioxide (CO₂), methane and water vapour trapping the sun’s heat in our atmosphere and warming our planet, Earth would be on average about 30°C cooler than the present day; uninhabitable to all but the hardiest of plants and animals. We need greenhouse gases, but recently human activities such as burning fossil fuels, the destruction of rainforests and intensive agriculture have led to substantial rises in the concentration of greenhouse gases in our atmosphere.

Over the last 10,000 years until the Industrial Revolution, CO₂ concentrations in the atmosphere remained at around 280 parts per million by volume (ppmv), after which they started to rise. By 1950, levels had increased to 300ppmv and currently atmospheric CO₂ is estimated to be around 385ppmv. A sharp rise can also be seen in many other greenhouse gases, such as methane and nitrous oxide. Although carbon dioxide is not as potent as some other gases at trapping heat, the sheer quantity of CO₂ that is emitted and the length of time that CO₂ can remain in our atmosphere (in excess of 100 years), mean that over two thirds of the projected warming during the 21st century will be due to increasing levels of CO₂ (IPCC, 2007).

It is useful to be able to look at how greenhouse gases influence the way our climate behaves when they are grouped together, rather than as individual gases. This is called the equivalent carbon dioxide (CO₂e) concentration. Today’s atmosphere has a CO₂e concentration of 434ppmv when the effects of CO₂, methane, nitrous oxide and other gases controlled under the Kyoto Protocol are combined. If the cooling effect of other pollutants in the atmosphere, such as aerosols, is also included, then the CO₂e concentration falls to about 388ppmv.

So What are the Projections for the 21st Century Climate?

Scientists use complex models, often run on supercomputers, to make projections about our future climate. However, there are always uncertainties in models; one of the most important is that we do not know how much CO₂ and other greenhouse gases might be emitted over the course of the 21st century. Other pollutants, such as aerosols, can have a significant effect on the atmosphere, often resulting in regional cooling. Predicting what pollutants might be emitted and in what concentrations is very difficult. Additionally, computer models cannot be infinitely complex or represent every interaction that may control our climate. Other uncertainties can arise from natural processes. For example, a large volcanic eruption, like that of Mount Pinatubo in the Philippines in 1991, can release huge amounts of dust and gas into the atmosphere, creating a cooling effect on the climate for a number of years. Even so, scientists can quantify some of these uncertainties, and by looking at how well the models replicate past changes in climate, they can project what may happen.

The following projections for the end of the 21st century are those presented by the Intergovernmental Panel on Climate Change in 2007 and the United Kingdom Climate Impacts Programme (2002).

Box 1.1 Worldwide Projections for the End of the 21st Century

• Global average annual surface temperature is expected to rise by between 1.1°C and 6.4°C (with respect to the 1980–1999 average under a range of emissions scenarios).
• Global sea level could rise by up to 60cm: local variations will result in greater rises in some regions and lower rises in others.
• Rainfall is very likely to increase in the high latitudes and many equatorial regions, while decreasing in parts of the tropics and subtropics.
• Sea ice is very likely to decrease in extent, while continental i...

Table of contents

• Cover Page
• Half Title page
• Title Page
• Copyright Page
• Contents
• About the Editors and Authors
• Foreword
• Acknowledgements
• List of Acronyms and Abbreviations
• Introduction
• Part I Information
• Part II Action
• Resources
• Index