Climate Change Adaptation in Small Island Developing States - Martin J. Bush - E-Book

Climate Change Adaptation in Small Island Developing States E-Book

Martin J. Bush

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A groundbreaking synthesis of climate change adaptation strategies for small island states, globally A wide ranging, comprehensive, and multi-disciplinary study, this is the first book that focuses on the challenges posed by climate change impacts on the Small Island Developing States (SIDS). While most of the current literature on the subject deals with specific regions, this book analyses the impacts of climate change across the Caribbean, the Pacific Ocean, and the African and Indian Ocean regions in order to identify and tackle the real issues faced by all the small island States. As the global effects of climate change become increasingly evident and urgent, it is clear that the impact on small islands is going to be particularly severe. These island countries are especially vulnerable to rising sea levels, hurricanes and cyclones, frequent droughts, and the disruption of agriculture, fisheries and vital ecosystems. On many small islands, the migration of vulnerable communities to higher ground has already begun. Food security is an increasingly pressing issue. Hundreds of thousands of islanders are at risk. Marine ecosystems are threatened by acidification and higher seawater temperatures leading to increased pressure on fisheries--still an important source of food for many island communities. The small island developing States emit only small amounts of carbon dioxide and other greenhouse gases. Yet many SIDS governments are allocating scarce financial and human resources in an effort to further reduce their emissions. This is a mistake. Rather than focus on mitigation (i.e., the reduction of greenhouse gas emissions) Climate Change Adaptation in Small Island Developing States concentrates on adaptation. The author assesses the immediate and future impacts of climate change on small islands, and identifies a range of proven, cost-effective adaptation strategies. The book: * Focuses on the challenges of climate change faced by all of the world's small island developing States; * Provides comprehensive coverage of the latest research into the most likely environment impacts; * Uses numerous case studies to describe proven, practical, and cost-effective policies, including disaster management strategies--which can be developed and implemented by the SIDS; * Takes a unique, multidisciplinary approach, making it of particular interest to specialists in a variety of disciplines, including both earth sciences and life sciences. This book is a valuable resource for all professionals and students studying climate change and its impacts. It is also essential reading for government officials and the ministries of the 51 small island developing States, as well as the signatories to the 2015 Paris climate agreement.

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Table of Contents

Cover

Title Page

Preface

Abbreviations and Symbols

1 The Changing Climate

Introduction

Recent Impacts of Climate Change

Reports From the Front Line

Future Shock

Warming the Oceans

Multidimensional Threats

References

2 Small Island Developing States

Meet the SIDS

Demography

Social Development

Economic Vulnerability

Climate Change Impacts on Small Islands

Coastal Zones: A Clear and Present Danger

Coastal Zones: Terrestrial and Intertidal Impacts

Coastal Marine Ecosystems

Low Elevation Coastal Zones

Agriculture

Fisheries

Food Insecurity

Undernourishment in the SIDS

Poverty and Climate Change

Tourism

Freshwater Resources

Human Health

Climate‐driven Migration

References

3 Adapting to a Changing Climate

Ecosystem‐based Adaptation

Adaptation in Coastal and Marine Environments

Marine Protected Areas

Three Bays Protected Area in Haiti

Climate Change Adaptation in Agriculture

Conservation Agriculture

Rice Production

Irrigation

Adaptation Technologies for Agriculture

Water Resources Management

Integrated Water Resources Management (IWRM)

Agricultural Water Management (AWM)

Rainwater Harvesting and Management

Wastewater Treatment and Recycling

Reclaimed Water for Agricultural Use

Fisheries and Aquaculture

Disaster Risk Management

Adaptation and Mitigation Synergies

References

4 Adapting Energy Systems

Depending on Energy

Access to Electricity

Renewable Energy

Photovoltaic (PV) Electricity

Minigrid Systems

Distributed PV Systems

Wind Power

Solar Water Heaters

Hydropower

Geothermal Energy

Solar Thermal Power

Energy Efficiency

References

5 Managing Adaptation

The Key Climate Hazards

The Regulatory Framework

National Adaptation Programs of Action

Financing Adaptation

The Green Climate Fund

The Adaptation Fund

Programme Development

Geographical Information Systems

References

6 Country Profiles

American Samoa

Anguilla

Antigua and Barbuda

Aruba

The Bahamas

Bahrain

Barbados

Belize

British Virgin Islands

Cabo Verde

Comoros

Cook Islands

Cuba

Dominica

Dominican Republic

Fiji

French Polynesia

Grenada

Guam

Guinea‐Bissau

Guyana

Haiti

Jamaica

Kiribati

Maldives

Marshall Islands

Mauritius

Micronesia, Federated States

Montserrat

Nauru

New Caledonia

Niue

Northern Mariana Islands

Palau

Papua New Guinea

Puerto Rico

Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines

Samoa

São Tomé and Príncipe

Seychelles

Singapore

Solomon Islands

Suriname

Timor‐Leste

Tonga

Trinidad and Tobago

Tuvalu

US Virgin Islands

Vanuatu

References

Index

End User License Agreement

List of Tables

Chapter 01

Table 1.1 Ocean warming: Its impact and consequences.

Table 1.2 Health impacts of climate change.

Table 1.3 Climate change impacts in the British Virgin Islands.

Chapter 02

Table 2.1 The geographical regions of the 51 Small Island Developing States.

Table 2.2 Basic data on the 51 SIDS.

Table 2.3 Human Development Indices for the SIDS.

Table 2.4 Threats to coastal zones of small islands.

Table 2.5 Storm surges recorded in the US this century (National Hurricane Center, 2015b).

Table 2.6 Coastal populations (thousands) at different elevations above mean sea‐level (metres).

Table 2.7 Coastal populations (percentages) at different elevations above mean sea‐level (metres).

Table 2.8 Islands that have more than 10% of land area at risk at LECZ3 (low elevation coastal zone – 3 metres).

Table 2.9 The importance of agriculture in the SIDS.

Table 2.10 Climate change impacts on fisheries.

Table 2.11 Coastal fisheries production and projected deficits for four Pacific island states.

Table 2.12 Undernourishment in 20 small island states.

Table 2.13 The 13 SIDS where international tourism receipts account for more than 20% of GDP.

Table 2.14 Projected changes in temperature and precipitation for the main SIDS regions (RCP4.5 annual projected change for 2081–2100 compared with 1986–2005).

Chapter 03

Table 3.1 Co‐benefits of ecosystem‐based adaptation measures.

Table 3.2 Responses to sea‐level rise.

Table 3.3 Typical MPA management plan.

Table 3.4 MPA objectives in the context of climate change.

Table 3.5 The communes defining the ridge to reef zone.

Table 3.6 Managing the threats to the Three Bays Protected Area.

Table 3.7 Rice paddy production in 25 SIDS.

Table 3.8 Adaptation technologies for agriculture.

Table 3.9 Lack of effective water resources management in SIDS.

Table 3.10 Examples of types of crops irrigated with treated wastewater.

Table 3.11 Levels of wastewater treatment and systems.

Table 3.12 Factors affecting the choice of irrigation system and special measures required for reclaimed water re‐use.

Table 3.13 Adaptation and mitigation synergies.

Chapter 04

Table 4.1 Dependency of SIDS on imported petroleum fuels for electrical power generation (2012).

Table 4.2 Five SIDS generating more than a third of their electricity from renewable energy sources (percentages).

Table 4.3 SIDS with less than 90% access to electricity (2012).

Table 4.4 Global average levelized cost of electricity for wind and solar.

Table 4.5 Electricity tariffs in Jamaica in 2011.

Table 4.6 Factors that facilitated market penetration of solar hot water heaters.

Chapter 05

Table 5.1 Ministries managing climate change action in Haiti.

Table 5.2 Number of sectoral projects proposed in the NAPAs of LDC SIDS.

Table 5.3 Multilateral climate funds.

Table 5.4 Bilateral climate funds.

Table 5.5 Adaptation Fund support to the SIDS.

Table 5.6 Outline of action plan for funding adaptation.

List of Illustrations

Chapter 01

Figure 1.1 Global mean temperature changes based on land and ocean data since 1880.

Figure 1.2 Atmospheric CO

2

concentrations measured by the NOAA since before 1960.

Figure 1.3 Global carbon dioxide budget over the period 2006 to 2015.

Chapter 02

Figure 2.1 Economic vulnerability of 33 SIDS.

Figure 2.2 Mangroves store huge amounts of carbon.

Figure 2.3 Reef Check surveys of Haiti.

Figure 2.4 A typical former coral reef at La Gonave in Haiti overfished to the point where it has become an algal dominated reef with a few stubs of coral surviving but no fish.

Figure 2.5 Storm surge and storm tide.

Figure 2.6 The island of Malé in the Maldives.

Figure 2.7 Climate and non‐climate factors influencing food security.

Chapter 03

Figure 3.1 Marine protected areas in small island developing states.

Figure 3.2 The limits of the Three Bays Protected Area.

Figure 3.3 Charcoal production from mangroves close to the PN3B.

Figure 3.4 Plastic bottles and floating garbage washed up on one of the small islands on the west coast of Haiti.

Figure 3.5 The seven watersheds linked to the Three Bays Protected Area (PN3B) in Haiti.

Figure 3.6 Mapping the impact flows over the watershed areas linked to the PN3B.

Figure 3.7 Mapping the impact flows over the coastal areas of the Three Bays Protected Area.

Figure 3.8 Soil conservation practices in Haiti.

Figure 3.9 Aquaculture production since 1950.

Figure 3.10 Projected trends in fish production to 2025.

Chapter 04

Figure 4.1 Investments in renewable energy technologies (billion $).

Figure 4.2 Global renewable energy investments in 2015 (billion $).

Figure 4.3 Levelized costs of electricity from renewable energy technologies in 2014.

Figure 4.4 Schematic outline of PV‐diesel hybrid system for rural electrification.

Figure 4.5 Typical load profile for a rural community.

Figure 4.6 The inauguration of the Les Anglais photovoltaic hybrid minigrid system on 1 June 2015.

Chapter 05

Figure 5.1 Key climate hazards identified by 137 countries.

Figure 5.2 Priority sectors for adaptation.

Figure 5.3 Integrating top‐down and bottom‐up approaches for an ecosystem‐based action plan. MDE, Ministry of Environment; CC, climate change; MARNDR, Ministry of Agriculture.

Guide

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Climate Change Adaptation in Small Island Developing States

 

Martin J. Bush

Toronto, Canada

 

 

 

 

 

 

 

 

 

 

 

 

This edition first published 2018© 2018 John Wiley & Sons Ltd

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions.

The right of Martin J. Bush to be identified as the author of this work has been asserted in accordance with law.

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Library of Congress Cataloging‐in‐Publication data applied for

ISBN: 9781119132844

Cover Design: WileyCover Image: © AnnWorthy/iStockphoto

 

 

 

This book is dedicated to all the young folk who have inherited a wounded and ailing planet. A huge responsibility has been placed upon your shoulders. My hope is that this book, and many others like it, will help you to find the courage and the strength to fight for the survival of planet Earth.

And to Anna Delia Jean, Michael, and Corry who have been very supportive and patient.

Preface

This book is about climate change and how small island states need to adapt to a climate that is rapidly evolving in ways that presents a multitude of existential threats.

As a group, the Small Island Developing States, the SIDS, produce relatively small amounts of greenhouse gases. There are one or two exceptions to this rule, but for nearly all the islands the quantities of carbon dioxide generated are miniscule. Even so, most of the small island states have committed scarce financial and human resources to reducing their emissions even further as part of their commitments under the Paris Agreement. This is a mistake.

The urgent priority for small island states is to find ways to adapt to the changing climate. Reducing their greenhouse gas emissions doesn’t help anyone on the islands, and doesn’t even do anything much for the planet.

For many small island communities, the changing climate threatens not just their way of life but their very existence. As sea level rises and storms intensify, many of the SIDS will become uninhabitable as groundwater resources become contaminated by seawater intrusion, and overwashed arable land is rendered infertile by the salinized soil. At the same time, fishing is becoming less productive for many coastal communities as coral reefs are bleached out, and wamer and more acidic ocean waters play havoc with marine species’ environment.

Many adaptation strategies exist for small islands. The majority will survive because most of their land is substantially above sea‐level. But they will lose much of their coastal areas to the rising oceans, and many coastal communities will be forced to move to higher ground. States that are multi‐island countries that include many islands and atolls will have to deal with entire communities that will elect to move en masse to another, more secure, neighbouring island. Managing the social disruption and conflict that will result from these migrations will be a major challenge for many island states.

The management of water resources is crucial. As temperatures rise and periods of drought become longer and more frequent, the abundant rainfall of intense storms must be collected, stored, and managed. Agriculture must adapt to a more variable and unpredictable climate, and become more efficient in the way it uses water. Where coastal tourism is an important component of the economy, ways must be found to provide reliable electrical power and adequate potable water for tourism infrastructure.

Strengthening the resilience of coastal and marine ecosystems is a top priority. Ecosystem‐based adaptation is always a no‐regret action that should be implemented in collaboration with coastal communities.

The one area where climate change mitigation and adaptation go hand in hand is in the transition away from carbon‐based fuels to renewable energy. Transitioning electrical power production to renewables such as photovoltaic electricity and wind power brings many important co‐benefits that strengthen the resilience of island communities, and enable them to cope better with the extreme weather that is a dominant feature of the changing climate.

Small island states are in an extremely vulnerable position. Only a few of the 51 small island states are wealthy; several are still developing countries. Most of them lack the human and financial resources necessary to effectively tackle the difficulties they face. Coordination among key ministries is poor, and planning is generally weak, unfocused, and inadequate.

As this book went to press, three major hurricanes swept though the Caribbean destroying almost everything in their path. Harvey, Irma and Maria caused enormous damage to many small Caribbean islands. It is a reminder once again that for most of the small island states, focusing on reducing carbon emissions is not the priority. Ways have to be found to adapt to an increasingly unpredictable and often violent climate.

Although the outlook for small island developing states is not good, there is much that can be done if governments are better organized, and ministries cooperate and coordinate their plans. Many islands simply lack effective leadership. This book is intended to help.

Abbreviations and Symbols

AIMS

Africa, Indian Ocean, Mediterranean and South China Sea: a group of the SIDS

bbl

Barrel: 42 US gallons (about 159 litres)

CA

Conservation agriculture

CARICOM

Caribbean Community

CC

Climate change

CDC

Centers for Disease Control (USA)

CO

2

Carbon dioxide

COP

Conference of the Parties (to the UNFCCC)

CSA

Climate‐smart agriculture

DA

Designated authority

DR

Dominican Republic

EBA

Ecosystem‐based adaptation

EEZ

Exclusive economic zone

ENSO

El Nino Southern Oscillation

ESM

Earth system model

EVI

Economic Vulnerability Index

GCF

Green Climate Fund

GCM

General circulation model

GDP

Gross domestic product

GHGs

Greenhouse gases (principally CO

2

, methane and nitrous oxide)

GIS

Geographical information system

Gt

Gigatonne (1 billion tonnes)

GtC

Gigatonne of carbon

GtCO

2

Gigatonne of carbon dioxide

GtCO

2

e

Gigatonne of carbon dioxide equivalent (includes other greenhouse gases)

GW

Gigawatt (1 billion watts)

GWh

Gigawatt‐hour (1 billion watt‐hours)

HDR

Human development report

IAM

Idealized assessment model

IFPRI

International Food Policy Research Institute

INDC

Intended Nationally Determined Contribution

IPCC

Intergovernmental Panel on Climate Change

IPP

Independent power producer

IUCN

International Union for the Conservation of Nature

kWp

Kilowatt peak

LDC

Less developed country

LECZ

Low elevation coastal zone

LED

Light‐emitting diode

MENA

Middle East and North Africa

MPA

Marine protected area

MSL

Mean sea‐level

MtCO

2

Million tonnes of CO

2

MW

Megawatt (1 million watts)

MWh

Megawatt‐hour (1 million watt‐hours)

MWp

Megawatt peak

NASA

National Aeronautical and Space Agency (USA)

NDA

National designated authority

NHC

National Hurricane Centre (USA)

NOAA

National Oceanic and Atmospheric Administration (USA)

pH

A measure of acidity (pH of 7 is neutral, a lower value is more acidic)

PN3B

Three Bays National Park (in Haiti)

PNG

Papua New Guinea

PPA

Power purchase agreement

ppb

Parts per billion

ppm

Parts per million

PV

Photovoltaic (energy)

RCP

Representative concentration pathway

RF

Radiative forcing

SIDS

Small Island Developing State

SST

Sea surface temperature

t/yr

Tonnes per year

UNDESA

United Nations Department of Economic and Social Affairs

UNFCCC

United Nations Framework Convention on Climate Change

WHO

World Health Organization

1The Changing Climate

Introduction

This introductory chapter outlines and summarizes the latest information and data about the Earth’s changing climate. It relies to a large extent on the fifth Assessment Report of the Intergovernmental Panel on Climate Change – the IPCC, the international scientific agency that reports every four or five years on climate change. But the chapter also integrates much of the most recent information on the impact of climate change, some of which suggests that the IPCC underestimates the threat to human welfare across the globe. The aim of the chapter is to look at the big picture in terms of the global impact of climate change. In subsequent chapters we will look at the impact of climate change on the different sectors of a country’s economy, and then specifically how climate change is an increasingly dangerous threat for Small Island Developing States (SIDS), and what measures can be taken to reduce the level of that threat.

The scientific evidence that human activity has influenced the climate system is overwhelming. The climate is changing and in ways that have never before been experienced in human history. The atmosphere and the oceans are warmer, continental areas of snow and ice have diminished, and sea‐levels have risen. These are well‐established scientific facts. Reliable climate data show that each of the last three decades has been successively warmer at the surface of the Earth than any preceding decade since measurements began over 150 years ago.

The evidence shows that the three decades before 2012 were the warmest period over several centuries in the northern hemisphere, and quite possibly the warmest period in more than a thousand years. Data measured by NASA and NOAA confirmed that 2014, and then 2015, were the hottest years on record. Then 2016 broke those records again. The year 2016 was the warmest on record in all the major global surface temperature datasets (NASA, 2015a; WMO, 2017).

The cryosphere is undergoing a huge transition: snow cover, sea ice, lake and river ice, glaciers, ice caps and ice sheets, permafrost and seasonally frozen ground, are all thawing and melting. Glaciers are melting almost everywhere and have contributed to sea‐level rise throughout the twentieth century. The rate of ice loss from the Greenland ice sheet has substantially increased over the last 20 years. Melting from the Antarctic ice sheet, mainly from the northern Antarctic peninsula and the Amundsen Sea sector of West Antarctica, has also increased. The extent of Arctic sea ice has decreased in every season, with the most rapid decrease taking place every summer. The trend continued in 2017 with the extent of the sea ice at both poles dropping to record levels. Never before in the satellite records has the area of sea ice at the north and south poles simultaneously fallen so dramatically. The summer Arctic sea ice minimum is decreasing by about 10–13% per decade – a figure that translates to around one million km2 each decade.

Snow cover has decreased in the northern hemisphere since the middle of the last century. In addition, because of the higher surface temperatures and changing snow cover, permafrost temperatures have increased in the northern hemisphere with commensurate reductions in thickness and area.

Figure 1.1 shows the trend in global mean temperatures since 1880 (NASA, 2015b).

Figure 1.1 Global mean temperature changes based on land and ocean data since 1880.

Source: Courtesy of NASA (2015b), http://data.giss.nasa.gov/gistemp/graphs/.

More than 90% of the thermal energy accumulated in the climate system over the last couple of decades has been absorbed and stored in the oceans. Only about 1% of this heat is held in the atmosphere.

Tracking ocean temperatures and the associated changes in ocean heat content allows scientists to monitor variations in the Earth’s energy imbalance. Ocean waters are getting warmer: the effect is greatest near the surface, and the upper 75 metres have been warming by over 0.1 °C per decade (IPCC, 2014a). But not only warmer: many large geographical areas of ocean water are becoming more saline as evaporation increases due to the higher surface temperatures. In contrast, other ocean areas, where precipitation is the dominant water cycle mechanism, may have become less saline.

These regional and differing trends in ocean salinity provide indirect evidence for widespread changes in evaporation and precipitation over the oceans, and by extension in the global hydrological cycle. These changes have major implications for rainfall patterns and intensities worldwide, and also for global patterns of ocean water circulation. As the lower atmosphere becomes warmer, evaporation rates increase, resulting in an increase in the amount of water vapour circulating throughout the troposphere. A consequence of this phenomenon is an increased frequency of intense rainfall events, mainly over land areas. In addition, because of warmer temperatures, more precipitation is falling as rain rather than snow – which has consequences for regional patterns of spring runoff.

As the oceans warm they expand, resulting in both global and regional sea‐level rise. The increased heat content of the oceans accounts for as much as 40% of the observed global sea‐level rise over the past 60 years.

The slow but steady change in the global water cycle has also had an impact on sea‐levels worldwide. Over the last century, global mean sea‐level rose by about 0.2 metres. The rate of sea‐level rise is also increasing: the rate now is greater than at any time during the last two millennia. NASA satellites have shown that sea‐levels are now rising at about 3 mm a year: a total of more than 50 mm between 1993 and 2010 (NASA, 2015c).

Some regions experience greater sea‐level rise than others. The tropical western Pacific saw some of the highest rising sea‐level rates over the period 1993–2015 – which became a significant factor in the extensive devastation of areas of the Philippines when typhoon Haiyan generated a massive storm surge in November 2013 (WMO, 2017).

The absorption of carbon dioxide (CO2) by ocean seawater, driven by higher atmospheric concentrations of the gas, has resulted in an increase in the acidity of the oceans. The acidity (pH) of ocean surface water has decreased by 0.1, which corresponds to a 26% increase in acidity, a change that many marine species cannot endure. In addition, as a result of the warming trend, oxygen concentrations have decreased in coastal waters and in many ocean regions.

Any changes in the Earth’s climate system that affect how much energy enters or leaves the Earth and its atmosphere alters the Earth’s energy equilibrium and will cause global mean temperatures to rise or fall. These changes, called radiative forcings (RF), quantify the variations in the amount of energy in the Earth’s climate system. Natural climate forcings include changes in the sun’s brightness, Milankovitch cycles (small variations in the Earth’s orbit and its axis of rotation), and large volcanic eruptions that inject dust and particulates high into the atmosphere and reduce incoming solar radiation.

However, the largest contributor to radiative forcing by far is the concentration of greenhouse gases (GHGs) in the atmosphere. Greenhouse gas emissions caused by human activities have increased markedly since the pre‐industrial era, driven largely by economic and population growth. From 2000 to 2010, GHG emissions were the highest in history, and have driven atmospheric concentrations of carbon dioxide, methane, and nitrous oxide to levels unprecedented in at least the last 800,000 years. Concentrations of carbon dioxide, methane, and nitrous oxide have all seen particularly large increases over the period from 1750 to the present day (IPCC, 2014a).

Carbon dioxide (CO

2

) levels have risen from about 280 parts per million (ppm) to 400 ppm in 2015.

Methane has more than doubled, rising from 700 per billion (ppb) to more than 1800 ppb.

Nitrous oxide has risen from about 270 ppb to more than 320 ppb.

At the beginning of this century, carbon dioxide concentrations increased at the fastest observed decadal rate of change. For methane, after almost a decade of stable concentrations since the late 1990s, atmospheric measurements have shown renewed increases since 2007. Nitrous oxide concentrations have also increased steadily over the last three decades.

Since 1970, cumulative CO2 emissions from fossil fuel combustion, cement production and flaring have tripled, while emissions from forestry and land use changes have increased by about 40%. Figure 1.2 tracks how emissions of CO2 have been constantly climbing for the last 60 years.

Figure 1.2 Atmospheric CO2 concentrations measured by the NOAA since before 1960.

Source: NOAA (2015). Courtesy of NOAA ESRL Global Monitoring Division.

Carbon dioxide is the predominant greenhouse gas, accounting for about three‐quarters of total GHG emissions. According to the IPCC, since the beginning of the industrial era about 2000 billion tonnes (Gt) of CO2 have been released into the Earth’s atmosphere (IPCC, 2014a). Of this total, approximately 40% of CO2 emissions remain in the atmosphere; the remainder is removed from the atmosphere by sinks or stored in natural carbon cycle reservoirs. Ocean absorption and storage in vegetation and soils account in about equal measure for the remainder of the CO2 emissions: the oceans absorb about 30% of the emitted CO2, which is what causes the increase in the acidity of ocean seawater.

Figure 1.3 shows how carbon dioxide moves around in the global carbon cycle (LeQueré et al., 2016). The numbers, in gigatonnes of carbon dioxide per year (Gt/yr), are averaged over the decade 2006–2015. The up arrows show emissions from fossil fuels and industry, and from land‐use change; the down arrows indicate carbon dioxide that is absorbed by the ‘sinks’: land and the oceans. The excess carbon dioxide remains in the atmosphere where it is accumulating constantly, as Figure 1.2 confirms.1

Figure 1.3 Global carbon dioxide budget over the period 2006 to 2015.

Source: LeQueré et al. (2016), www.earth‐syst‐sci‐data.net/8/605/2016/. Used under CC‐BY‐3.0.

In the twenty‐first century, emissions of GHGs have increased substantially, with larger absolute increases between 2000 and 2010. In spite of the increasing number of climate change mitigation policies implemented worldwide, annual GHG emissions grew on average by 2.2% annually from 2000 to 2010 compared with 1.3% per year from 1970 to 2000. Recent GHG emissions are the highest in human history; the global economic crisis of 2007/2008 reduced emissions only temporarily (IPCC, 2014a). Total anthropogenic GHG emissions from 2000 to 2010 were the highest ever recorded, reaching 49 GtCO2e in 2010 and then rising to over 52 GtCO2e in 2014 (UNEP, 2016).

Greenhouse gas emissions have levelled off since about 2012, due to the shift to cleaner carbon fuels, huge investments in renewable energy, and the increased efficiency in the way energy is used, but the present level of emissions is still far above the much lower levels needed to keep the Earth’s atmospheric temperatures below the Paris target of 2 °C. Emissions need to not just flatline: they need to fall precipitously. There is no sign yet that this is happening.

Although radiative forcing has been increasing at a lower rate over the period 1998 to 2011, this is partly due to cooling effects from volcanic eruptions and the cooling phase of the solar cycle between 2000 and 2009. For the period from 1998 to 2011, most climate model simulations show a surface warming trend that is greater than the observations. This difference is thought to be caused by natural internal climate variability, which sometimes enhances and sometimes counteracts the long‐term forced warming trend. Natural internal variability can therefore reduce the reliability of short‐term trends in long‐term climate change. However, for the longer period between 1951 and 2012, simulated surface warming trends are consistent with observed values.

Recent Impacts of Climate Change

The global climate has been changing for the last several decades, but the changes have become increasingly evident, recorded in more detail and better understood. Mean global surface temperatures are now more than 1 °C higher than they were in pre‐industrial times, and impacts from climate change have been recorded on natural and human systems on all continents and across all the oceans. The impact of climate‐related extremes include the degradation of ecosystems, the disruption of food production and water supply, damage to infrastructure and human settlements, increased sickness and mortality, and negative effects on mental health and wellbeing. The information below summarizes observed climate‐change related events over the last few years for seven regions of the world (IPCC, 2014b; WMO, 2017).

In Africa, recent observations attributed to climate change include:

Extreme heatwaves and drought in southern Africa from late 2015 to early 2016.

The retreat of tropical highland glaciers in East Africa.

Lake surface warming and water column stratification increases in the Great Lakes and Lake Kariba.

Increased soil moisture drought in the Sahel since 1970, although partially wetter conditions since 1990.

Tree density decreases in western Sahel and semi‐arid Morocco.

Range shifts of several southern plants and animals.

Decline in coral reefs in tropical African waters.

In Europe:

Increasingly frequent heatwaves (temperatures in Spain reached 45.4 °C in September 2016).

The retreat of Alpine, Scandinavian and Icelandic glaciers.

Increase in rock slope failures in the western Alps.

Earlier greening, leaf emergence, and fruiting in temperate and boreal trees.

Increased colonization of alien plant species.

Earlier arrival of migratory birds since 1970.

Increasing burnt forest areas during recent decades in Portugal and Greece.

Northward distributional shifts of zooplankton, fishes, seabirds and benthic invertebrates in NE Atlantic.

Northward and depth shift in distribution of many fish species across European seas.

Plankton phenology changes in NE Atlantic.

Spread of warm water species into the Mediterranean beyond changes due to invasive species and human impacts.

Impacts on livelihoods of Sami people in northern Europe.

Stagnation of wheat yields in some countries in recent decades despite improved technology.

Positive yield impacts for some crops mainly in northern Europe.

Spread of bluetongue virus in sheep and ticks across parts of Europe.

In Asia:

Permafrost degradation in Siberia, Central Asia and the Tibetan plateau.

Shrinking mountain glaciers across most of Asia.

Increased flow in several rivers due to shrinking glaciers.

Earlier timing of spring floods in Russian rivers.

Reduced soil moisture in northern China (1950–2006).

Surface water degradation in parts of Asia.

Changes in plant phenology and growth in many parts of Asia.

Distribution shifts of many plant and animal species upwards in elevation or poleward.

Advance of shrubs into the Siberian tundra.

Decline in coral reefs in tropical Asian waters.

Northward range extension of corals in the East China Sea and western Pacific, and of predatory fish in the Sea of Japan.

Negative impacts on aggregate wheat yields in south Asia.

In Australasia:

Significant decline in late‐season snow depth at three out of four alpine sites (1957–2002).

Substantial reduction in ice and glacier ice volume in New Zealand.

Reduced inflow in river systems in SW Australia since mid‐1970s.

Changes in genetics, growth, distribution and phenology of many species particularly birds, butterflies and plants.

Expansion of monsoon rainforest at the expense of savannah and grasslands in northern Australia.

Changed coral disease patterns at the Great Barrier Reef and widespread coral bleaching.

Advanced timing of wine grape maturation in recent decades.

In North America:

Shrinkage of glaciers across western and northern areas.

Decreasing amount of water in spring snowpack in western areas.

Shift to earlier peak flow in snow‐dominated rivers in western areas.

Phenology changes and species distribution shifts upward in elevation and northward across multiple taxa.

Increased wildfire frequency in subarctic conifer forests and tundra.

Northward distributional shifts of northwestern fish species.

Changes in mussel beds along the west coast.

Changed migration and survival of salmon in northeast Pacific.

Increased coastal erosion in Alaska and Canada.

Impacts on livelihoods of indigenous groups in the Canadian Arctic.

In Central and South America:

Shrinkage of Andean glaciers.

Changes in extreme flows in the Amazon River.

Changing discharge patterns in rivers in the western Andes.

Increased streamflow in sub‐basins of the La Plata River.

Increase coral bleaching in the western Caribbean.

More vulnerable livelihood trajectories for indigenous Aymara farmers in Bolivia due to water shortages.

Increase in agricultural yields and expansion of agricultural areas in southeastern South America.

In the polar regions, changes attributed to climate change are widespread:

Decreasing Arctic sea ice cover in summer.

Reduction in ice volume in Arctic glaciers.

Decreasing snow cover extent across the Arctic.

Widespread permafrost degradation especially in the Southern Arctic.

Ice mass loss across coastal Antarctica.

Increased winter minimum river flow in most of the Arctic.

Increased lake water temperatures and prolonged ice‐free seasons.

Disappearance of thermokarst lakes due to permafrost degradation in the low Arctic.

New lakes created in areas of formerly frozen peat.

Increased shrub cover in tundra in North America and Eurasia.

Advance of Arctic tree line in latitude and altitude.

Changed breeding area and population size of subarctic birds due to snowbed reduction and/or tundra shrub encroachment.

Loss of snowbed ecosystems and tussock tundra.

Impacts on tundra animals from increased ice layers in snow pack, following rain‐on‐snow events.

Increased plant species ranges in the West Antarctic Peninsular and nearby islands over the past 50 years.

Increased phytoplankton productivity in Signy Island lake waters.

Increased coastal erosion across Arctic.

Negative effects on non‐migratory Arctic species.

Decreased reproductive success in Arctic seabirds.

Reduced thickness of foraminiferal shells in southern oceans due to ocean acidification.

Reduced krill density in Scotia Sea.

All the observations cited above are those where IPCC scientists are confident that they are primarily due to climate change, and not to other local and regional factors that have impacted the environment and ecosystems.

Reports From the Front Line

In 2015, 189 countries filed communications with the UNFCCC secretariat in advance of the 21st Conference of Parties (COP 21) held in Paris in December of that year. One hundred and thirty‐five of those countries included information about their adaptation programmes, the climate change impacts they were already experiencing, and their assessment of their vulnerability to the way the climate is changing (UNFCCC, 2016).

In terms of observed changes, many countries reported on the temperature increases in their territories, ranging from around 0.5 to 1.8 °C since the 1960s. Others referred to the rate of change of temperature per annum or over decades. Some countries referred to observed sea‐level rise, ranging from 10–30 cm in the past 100 years, or 1.4–3 mm per year.

Other observed changes highlighted by many countries included: increased frequency of extreme weather, in particular floods and drought; changes, mostly negative, in rainfall patterns; and increased water scarcity. For instance, one country reported that water availability per capita is now three times lower than in 1960, while another country indicated that annual maximum rainfall intensity in one hour increased from 80 mm in 1980 to 107 mm in 2012. One country reported that some of the islands in its territory have disappeared under water, while another referred to the near‐disappearance of Lake Chad.

Most of the communications submitted by these countries contain a description of the key climate hazards faced by the countries concerned. The three main sources of concern are flooding, droughts and higher temperatures. Many countries have observed extreme weather such as stronger wind and rain, cyclones, typhoons, hurricanes, sea storm surges, sandstorms and heatwaves. Countries also mentioned slow‐onset impacts such as ocean acidification and coral bleaching, saltwater intrusion and changes in ocean circulation patterns, desertification, erosion, landslides, vector‐borne disease, as well as the high risk of glacial lake outburst floods.

The most vulnerable sectors most referred to by all the countries were water, agriculture, biodiversity and health. Forestry, energy, tourism, infrastructure and human settlement are also identified as vulnerable by a number of countries, and wildlife was mentioned by at least three.

In terms of the most vulnerable geographical zones: arid or semi‐arid lands, coastal areas, river deltas, watersheds, atolls and other low‐lying territories, isolated territories and mountain ranges are all identified in the reports, and some countries identified specific regions that were most vulnerable. Two countries stressed that they were at risk of losing significant amounts of economically important land in river deltas due to sea‐level rise.

Vulnerable communities were identified as being mostly composed of rural populations, in particular smallholders, women, youth and the elderly. Several countries provided quantitative estimates of vulnerable people or communities, sometimes using specific indicators. One country identified 319 municipalities as highly vulnerable; another categorized 72 of its 75 districts as highly vulnerable and identified specific risks. One country stated that 42 million people might be affected by sea‐level rise due to its long coastline.

In addition to climate impacts, many countries referred to the social, economic and political consequences of a changing climate. Many referred to the risk of fluctuating food prices and other related risks such as the declining productivity of coral reef systems, reduced crop yields or fishing catches, as well as to water security challenges due to scarcity or contamination. For instance, one country stated that that the flow of the Nile is projected to decrease by 20–30% in the next 40 years, creating serious water supply concerns. Others are concerned about the loss of pastoral land, and some countries fear that changes in precipitation and the growing season may disrupt their agricultural calendars. Other drew attention to specific threats to infrastructure and property. In this context, a few countries drew attention to concerns for social justice, stressing that high‐risk areas are often populated by the poorest and most marginalized segments of society. A few countries are recovering from conflicts and indicated that climate change poses an additional burden on their fragile state. Two countries highlighted that water scarcity has triggered conflicts between nomadic peoples or pastoral communities (UNFCCC, 2016).

The Caribbean drought of 2009–2010

Perhaps linked to a strong El Nino in 2009, the drought impacted all the islands from the Bahamas down to Guyana. St Lucia declared a water emergency after its main reservoir’s level dropped more than six metres. Two schools and several courtrooms were forced to close because of dry taps. In Guyana, a grass‐roots women’s organization staged a protest and fundraiser to purchase a water truck. In Jamaica, where the island’s largest dams had been operating at less than 40% capacity, inmates at a maximum security prison protesting the lack of water started a riot that injured 23 people. Incidents of water theft, illegal connections and vandalism shot up. Trinidad and Tobago enforced a strict water conservation law for the first time in 20 years. In Barbados, crews battled more than 1000 bush fires – nearly triple the number of the previous year.

Future Shock

Scientists have been building mathematical models of the Earth’s geophysical and socioeconomic systems since computers became capable of handling the mathematics and data storage requirements back in the late 1960s. Perhaps the most famous global model was the World3 model developed by Donella Meadows and her colleagues, which led to the publication of the book The Limits to Growth in 1972. Since that time, mathematical models of global and regional geophysical systems have become much more complex and now require massive amounts of computing power.

The IPCC climate models are mathematical representations of the geophysical processes that drive the Earth’s climate system. The models range from simple idealized models to comprehensive general circulation models (GCMs), including Earth system models (ESMs) that simulate the carbon cycle. The models are extensively tested against historical observations to confirm their accuracy, and to enable adjustments of their parameters if their accuracy falls short.

Climate models perform well in reproducing observed continental‐scale surface temperature patterns and multi‐decadal trends, including the more rapid warming since the mid‐twentieth century, and the cooling immediately following large volcanic eruptions. The simulation of large‐scale patterns of precipitation has been less successful and models perform less well for rainfall than for surface temperatures. The ability to simulate ocean thermal expansion, changes in glacier mass and ice sheets, and thus sea‐level, has improved since the previous IPPC assessment report in 2007, but difficulties remain in accurately modelling the dynamics of the Greenland and Antarctic ice sheets. However, recent improvements and advances in scientific understanding have resulted in more reliable sea‐level projections (UNEP, 2015).

The projections of future climate change are based on information described in scenarios of greenhouse gas and air pollutant emissions and land‐use patterns. Scenarios are generated by a range of approaches, from simple idealized experiments to the more complex ‘idealized assessment models’ (IAMs). The key factors incorporated into the models are economic and population growth, lifestyle and behavioural changes, changes in energy consumption and land use, new technology and climate policy. The standard scenarios used in the IPCC's 5th Assessment Report are called Representative Concentration Pathways or RCPs.

In the IPCC scenarios, there are four RCPs, each projecting a different pathway of greenhouse gas and air pollutant emissions into the final decades of the twenty‐first century. They include a strict mitigation scenario, RCP2.6, two intermediate scenarios, RCP4.5 and RCP6.0, and one business‐as usual scenario with continuing high GHG emissions: RCP8.5. RCP2.6 represents a scenario that aims to keep global warming to not more than 2 °C above pre‐industrial era temperatures. This scenario requires substantial global reductions in GHG emissions to take place in the first quarter of the twenty‐first century, and net negative GHG emissions by 2100 – meaning that more greenhouse gases are sequestered than released into the environment, but this can only happen if GHG emissions are driven down to very low levels.

The business‐as‐usual scenario, RCP8.5, leads to global temperature increases of more than 4 °C by the end of the century – a situation that most experts consider will be close to catastrophic.

Which of the four RCP scenarios is the more likely? The RCP8.5 scenario is close to a business‐as‐usual scenario and that now seems unlikely, given the substantial international effort now underway to reduce GHG emissions and to mitigate the impact of climate change. The minimum impact scenario, RCP2.6, seems overly optimistic. It is based on the assumption that climate mitigation measures are widely implemented, and that they start to have a measurable impact within the next few years and definitely before 2020.

The most probable concentration pathway between now and the end of the twenty‐first century is therefore likely to be represented by one of the intermediate scenarios: RCP4.5 or RCP6.0, or somewhere in between. These RCP scenarios lead to increased surface temperatures of between 2 and 3 °C before the end of the century.

But higher mean global temperatures are certainly not impossible. In the absence of near‐term and much stronger mitigation actions and further commitments to reduce emissions, analyses in 2014 suggested that the likelihood of 4 °C warming being reached or exceeded this century had increased. According to a World Bank study at the time, there was about a 40% chance of exceeding 4 °C by 2100, and a 10% chance of exceeding 5 °C (World Bank, 2014).

The 2015 climate change agreement negotiated in Paris by over 180 countries was rightly celebrated as an historic agreement. The aim is to keep global warming to under 2 °C, although the governments of many small island states argued persuasively that even 2 °C of warming is too high: they insisted that an increase of 1.5 °C should be the absolute limit.

Unfortunately, it soon became apparent that even the 2 °C target was unlikely to be met. In May 2016, only a few months after the historic signing of the agreement, the UNFCCC acknowledged that CO2 emissions would continue to rise until at least 2030:

If only the unconditional components of the INDCs are taken into account, global total emissions are projected to be 55.6 (53.1 to 57.3) GtCO2e in 2025 and 57.9 (54.4 to 59.3) GtCO2e in 2030, while including the conditional components of the INDCs lowers the estimated levels of such emissions to 54.1 (51.4 to 55.8) GtCO2e in 2025 and 55.5 (52.0 to 57.0) GtCO2e in 2030.

In other words, even under the most optimistic scenario where substantial international funding enables all the conditional‐based action to be implemented and achieved, CO2 emissions will continue to increase over the next 15 years with no sign that they will even level out (UNFCCC, 2016).

Disaster risk management in Cuba

Cuba has made disaster risk management a high priority and set up an effective preparedness system. In 1963, Hurricane Flora caused 1200 fatalities; 25 years later, Hurricane George, just as strong, killed just four people in Cuba as opposed to 600 people in other countries in the region. In 2008, Hurricanes Ike and Gustav, which together claimed almost 350 lives in other countries in the Caribbean, killed only seven people in Cuba.

The Cuban government has addressed the problem of disaster management at all levels. The Civil Defence System has evolved, and in 2005 the Joint Staff of National Defence (EMNDC), with the support of the UNDP, founded Risk Reduction Management Centres (RRMCs). These centres are responsible for conducting research, collecting data, checking vulnerability, disseminating information, coordination and preparedness. Education on disaster risk management has integrated awareness and preparedness into the social fabric of society. As a result, people are in a position to analyze the data available individually to gauge the potential threat. Coordination and constant citizen engagement are the twin pillars of successful disaster risk management in Cuba.

In 2012, Hurricane Sandy destroyed more than 300 000 homes and affected more than 3 million people in Cuba. Despite the strength of the storm, Hurricane Sandy claimed only 11 lives in Cuba, while other countries suffered a total death toll of 285.

Source: UNDESA (2014).

Warming the Oceans

Most of the discussion about climate change has focused on the warming of the atmosphere – certainly this was the focus of attention at the December 2015 meeting in Paris. But the warming of the oceans is actually the real problem, and one that has only recently come into serious focus. A detailed report issued by the IUCN in 2016 examined the consequences of ocean warming in considerable detail (Laffoley & Baxter, 2016).

The oceans of water on planet Earth hold truly enormous quantities of thermal energy: on a volumetric basis, the heat capacity of water is roughly 4000 times that of air. What this means is that the oceans are an immense heat sink. Over 90% of the increased thermal energy generated by the Earth’s present energy imbalance is estimated to have been absorbed by the oceans. This enormous heat sink has huge thermal inertia, effectively buffering the atmosphere from rapid fluctuations in temperature. The constant movement of ocean water also distributes heat around the planet, transporting heat away from the tropics towards the poles. But even though the water temperatures are increasing extremely slowly, they can be measured and correlated. The trend is clear. The effects of ocean warming on the global environment are summarized by the IUCN in Table 1.1.

Table 1.1 Ocean warming: Its impact and consequences.

Source: Adapted from Laffoley & Baxter (2016). Reproduced with permission of the International Union for Conservation of Nature.

Ocean warming effect

Probable impacts

Changes in ocean heat content (OHC)

Increasing uptake of heat by the ocean as a response to the Earth’s energy imbalance buffering atmospheric warming

Rising water temperatures at all depths

Intensification of El Nino events

Warming of adjacent land masses

Warmer land surface temperatures

Melting permafrost

Retreating mountain glaciers and surface melting of the Greenland ice sheet

Terrestrial vegetation changes

Increased extent and magnitude of forest fires

Rising sea‐levels due to expansion of water with temperature plus melting ice sheets and glaciers

Permanent inundation of coastal areas and low‐elevation islands and atolls

Increased coastal flooding from storm surges

Saltwater intrusion into aquifers

Melting cryosphere (the frozen world)

Basal melting and thinning of ice shelves in Antarctica destabilizing dammed‐up ice sheet glaciers

Increased overall Antarctic ice mass and sea ice

Accelerated mass loss of the Greenland Ice Sheet including basal melting of marine terminating glaciers

Accelerating reduction of sea ice in the Arctic and in the Bellinghausen/Amundsen Sea of Antarctica

Intensification of the hydrological cycle

Enhanced atmospheric moisture transport towards the poles

Rising humidity and increasing precipitation

Increased Eurasian river discharges

Extreme droughts and floods

Both negative and positive feedbacks to global warming

Salinity increasing where evaporation dominates in the mid latitudes and decreasing in the rainfall‐dominated regions of the tropical and polar seas

Negative feedback on the ocean carbon sink

Higher sea surface temperature reduces CO

2

uptake from the atmosphere, increasing the rate of increase of atmospheric CO

2

Deoxygenation

Reduced oxygen solubility in warmer water

Reduced penetration of oxygen into deeper water due to enhanced stratification

Acidification

Rising temperatures reinforces ocean acidification

More extremes in natural variability such as the El Nino/Southern Oscillation (ENSO) and in weather events

Changes in the occurrence, frequency and severity of cyclones/hurricanes

Changes in the location and meandering of jet streams affecting downstream weather

Landslides, collapses in fisheries

Coral bleaching, enhanced disease prevalence, malnutrition and human migration

Monsoons, forest fires and associated air pollution

Changes in biological processes at cellular to ecosystem scales

Reduction and possible collapse of fisheries

Increasing food insecurity

Multidimensional Threats

There are essentially ten different types of threat caused or exacerbated by climate change.

Sea‐level rise and coastal flooding.

Populations, economic activity and infrastructure in low‐lying coastal zones are vulnerable. Urban populations are frequently unprotected due to substandard housing and inadequate insurance. Marginalized rural communities with multidimensional poverty and limited alternative livelihoods and coping mechanisms are particularly at risk. Rising sea‐levels contribute to seawater intrusion into freshwater aquifers. Island populations are extremely vulnerable to this threat.

Extreme precipitation and inland flooding.

Large numbers of people in urban areas are exposed to flood events, particularly in low‐income informal settlements and shanty towns. Poorly maintained and inadequate urban drainage infrastructure may have limited ability to cope.

Systemic failures.

Populations and infrastructure exposed and lack historical experience with hazards such as electrical distribution system failures, communication systems failures, health and emergency response systems collapse.

Increasing frequency and intensity of extreme heat, including heat island effects.

Extreme heat events are expected to increase in frequency and to impact a larger area of land. Urban populations of the elderly, the very young, expectant mothers, and people with chronic health problems in settlements are incapacitated by higher temperatures. Local organizations that provide health, emergency, and social services are unable to adapt effectively to new risk levels for vulnerable groups. Heatwaves are now a growing global threat, killing thousands of people each year (

The Lancet

, 2015b). In the US, a 2016 estimate of deaths from extreme events over the period 2004–2013 showed that heatwaves cause more fatalities than more spectacular events such tornadoes and hurricanes (USGCRP, 2016).

Warming, drought and precipitation variability.

Changes in precipitation will occur with continued warming, with substantial adverse consequences for the availability of water in many regions. Poorer communities in urban and rural settings are increasingly susceptible to food insecurity, particularly subsistence farmers and people in low‐income, agriculturally dependent economies. There may be limited ability to cope among the elderly and female‐headed households. Terrestrial ecosystems will be stressed and less productive; the services they provide to local communities will be disrupted.

Drought. Crop yields are already declining in many regions.

Reduced yields and production losses increase rapidly above 1.5–2 °C warming. Urban populations with inadequate water services, existing water shortages and supply problems are likely to be severely impacted. Poor farmers in dry lands or pastoralists with insufficient access to drinking and irrigation water will suffer. Limited ability to compensate for losses in water‐dependent farming and pastoralist systems will engender conflict.

Rising ocean temperatures and acidification.

Warm‐water coral reefs are highly susceptible to both increased temperatures and higher levels of acidity. Marine ecosystems on which coastal communities depend will deteriorate. Invasive marine species will proliferate.

Wildfires.

Although not usually on the list of threats driven by climate change, there is increasing evidence that wildfires, forest fires and bush fires are increasing in extent, frequency and ferocity. In 2015, the worst year on record, there were over 100,000 wildfires worldwide, including massive forest fires in Indonesia that could clearly be seen from space, and which generated so much smoke and air pollution across Indonesia, Singapore and Malaysia that the health impact on those populations is certain to be significant – not to mention the impact on wildlife in the forests that are destroyed (De Groot, 2015; GFED, 2015).

Societal upheaval and strife.

There is clear evidence that climate change is already affecting livelihoods in many regions of the world. Climate change has a greater adverse impact on poorer communities that are less able to cope and adapt. Coastal zones will become increasingly threatened by inundation and extreme weather, while at the same time livelihoods that depend on agriculture and fishing will become more difficult and less viable. Many communities will be forced to move and conflict between social groups will be inevitable. The competition for resources, particularly water, will become sharper. Climate‐change driven migration is increasingly becoming an international issue (

The Lancet

, 2015b).

Health.

The health impacts of climate change have only recently been coming into focus. They include malnutrition, impacts on mental health, increased levels of cardiovascular disease, respiratory disease, and vector‐borne diseases (

The Lancet

, 2015a).

The impacts of climate change on health are summarized in Table 1.2. This analysis is from a report that focused on the US, but the consequences of the changing climate on human health are global (USGCRP, 2016).

Table 1.2 Health impacts of climate change.

Threats

Climate change

Exposure

Health outcome

Impact

Extreme heat

More frequent, severe and prolonged heat events

Elevated temperature

Heat‐related death and illness

Rising temperatures will lead to an increase in heat‐related deaths and illnesses

Outdoor air quality

Increasing temperatures and changing precipitation patterns

Worsened air quality (ozone, particulates, and higher pollen counts)

Premature death, acute and chronic cardiovascular and respiratory illnesses

Rising temperatures and wildfires are decreasing precipitation which will lead to increases in ozone and particulate matter, elevating the risks of cardiovascular and respiratory illnesses and death

Flooding

Rising sea‐levels and more frequent or intense extreme precipitation, hurricanes, and storm surge events

Contaminated water, debris and disruptions to essential infrastructure

Drowning, injuries, mental health consequences, gastrointestinal and other illnesses

Increased coastal and inland flooding exposes populations to a range of negative health impacts before, during and after events

Water‐borne infections (Lyme disease)

Changes in temperature extremes and seasonal weather patterns

Earlier and geographically expanded tick activity

Lyme disease

Ticks will show earlier seasonal activity and a generally northward range expansion, increasing risk of human exposure to Lyme‐disease carrying bacteria

Water‐related infection (

Vibrio unifaces)

Rising sea surface temperatures, changes in precipitation and runoff affecting coastal salinity

Recreational water or shellfish contaminated with

Vibrio vulnificus

Vibrio vulnificus

induced diarrhoea and intestinal illness, wound and blood‐stream infections, death

Increases in water temperatures will alter timing and location of

Vibrio vulnificus

growth, increasing exposure and risk of water‐borne illness

Food‐related infection

(Salmonella)