Adapting Agriculture to Climate Change

Preparing Australian Agriculture, Forestry and Fisheries for the Future

Chris Stokes, Mark Howden, Chris Stokes, Mark Howden

• Publisher: CSIRO PUBLISHING
• Year: 2010
• ISBN:
  9780643102057
• Topic: Technology & Engineering
• Subtopic: Sustainable Agriculture
• Index: Technology & Engineering

Adapting Agriculture to Climate Change is a fundamental resource for primary industry professionals, land managers, policy makers, researchers and students involved in preparing Australia's primary industries for the challenges and opportunities of climate change.

More than 30 authors have contributed to this book, which moves beyond describing the causes and consequences of climate change to providing options for people to work towards adaptation action. Climate change implications and adaptation options are given for the key Australian primary industries of horticulture, forestry, grains, rice, sugarcane, cotton, viticulture, broadacre grazing, intensive livestock industries, marine fisheries, and aquaculture and water resources. Case studies demonstrate the options for each industry.

Adapting Agriculture to Climate Change summarises updated climate change scenarios for Australia with the latest climate science. It includes chapters on socio-economic and institutional considerations for adapting to climate change, greenhouse gas emissions sources and sinks, as well as risks and priorities for the future.

1

INTRODUCTION

SM Howden and CJ Stokes

KEY MESSAGES:

The climate is changing and further change seems unavoidable, even if efforts are taken to reduce greenhouse gas emissions. For primary industries to continue to thrive in the future we need to anticipate these changes, be prepared for uncertainty, and develop adaptation strategies now.

Some broad generalisations can be made about how plant growth, which underpins all the primary industries addressed in this book, will be affected by climate change. Warmer temperatures may benefit perennial plants in cool climates, but annuals and plants growing in hot climates may be negatively affected. Plant productivity would be expected to increase or decrease in accordance with any changes in rainfall, while the direct effects of CO₂ in stimulating plant growth and increasing water use efficiency could help by partly offsetting increases in evaporation or decreases in rainfall.

While there are some general principles about how impacts of climate change will vary geographically, regional climate change projections are currently more useful for describing the wide range of uncertainty and for probability-based risk assessment than serving as precise estimates for predictive planning and decision making.

Adaptation will need to take a flexible, risk-based approach that incorporates future uncertainty and provides strategies that will be able to cope with a range of possible changes in local climate. Initial efforts in preparing adaptation strategies should focus on equipping primary producers with alternative adaptation options suitable for the range of uncertain future climate changes and the capacity to evaluate and implement these as needed, rather than focussing too strongly yet on exactly where and when these impacts and adaptations will occur.

In the short term, a common adaptation option will be to enhance and promote existing management strategies for dealing with climate variability. This will automatically track early stages of climate change until longer term trends become clearer.

A changing climate for agriculture

Australia’s climate has many influences: seasonal synoptic circulations and frontal systems, the El Niño-Southern Oscillation (e.g. Pittock 1975), the Indian Ocean Dipole (Saji et al. 1999), the Southern Annular Mode (Marshall 2003), the Madden-Julian Oscillation (Donald et al. 2006), and the Inter-decadal Pacific Oscillation (Power et al. 1999) among others (see Table 1.1). Jointly, these have provided Australia with the world’s most variable climate. Managing the impacts of climate variability on agricultural systems has thus been a major challenge since European settlement but has been improving gradually. Now, in addition to this highly variable and challenging climate, there is increasing evidence that the climate is changing and that humans are likely to be the cause of this change (Solomon et al. 2007). Climate change will likely cause a range of impacts on Australian agriculture with a consequent need for adaptation responses to emergent risks and opportunities. This book is intended to be a first step towards effective climate change adaptation responses across Australian agriculture.

It is very likely that human-influenced emissions of greenhouse gases are affecting the global climate (Solomon et al. 2007). Global mean temperatures have risen approximately 0.76°C since the mid-1800s. The last decade is the warmest ever recorded instrumentally (0.42°C above the 1961–1990 baseline: Brohan et al. 2006) followed by the previous two decades (0.18 and 0.05°C respectively) while the last 100 years were the warmest of the millennium. This warming plus changes in continental-scale temperatures, rainfall patterns, wind fields, climate extremes and sea levels cannot be explained by natural causes alone: there is a strong human ‘fingerprint’ (Solomon et al. 2007). Additionally, rates of glacial and ice-field retreat and many other observations of physical and biological responses are consistent with expectations of ‘greenhouse’ climate change. It seems likely that these changes will continue for the foreseeable future due to ongoing, and even accelerating (Canadell et al. 2008) emissions of carbon dioxide and other greenhouse gases. Indeed, past greenhouse gas emissions alone are estimated to have committed the globe to a warming of about 0.2°C per decade for the next several decades (Solomon et al. 2007). The most up-to-date climate projections are for an increase in global average temperatures of 1.1–6.4°C by the end of the present century along with a large range of other climate changes (see Chapter 2). To place these temperature rises in perspective, a 1°C rise in average temperature will make Melbourne’s climate something like that currently experienced by Wagga Wagga, a 4°C rise like that of Moree and a 6°C rise like that just north of Roma in Queensland (corresponding to shifts in latitude of 2.5°, 8° and 11° towards the equator respectively). Intuitively, it is hard to conceive that such changes will not have implications for Australia’s agricultural industries. Unfortunately, at the moment the rate of greenhouse gas emissions, the build-up of atmospheric carbon dioxide, the global temperature increase and the rate of sea level rise are all at or above the worst-case scenario of the IPCC (Rahmstorf et al. 2007; Canadell et al. 2008) and thus the higher end of the range of change seems more likely than the lower.

Agricultural adaptation to climate change: a new need

Agricultural systems in Australia are well known to be sensitive to both long-term climatic conditions and year-to-year climate variability. This is evident in the systems used in a given geographic location or season type, average production and production variability, product quality, relative preferences for different agricultural activities, preferred soil types, the management systems and technologies used, input costs, product prices and natural resource management. Consequently, if the climate changes, there are likely to be systemic changes (or adaptations) in agricultural systems. Here we use the term ‘adaptation’ to include the actions of adjusting practices, processes and capital in response to the actuality or threat of climate change, as well as responses in the decision environment, such as changes in social and institutional structures, or altered technical options, that can affect the potential or capacity for these actions to be realised (Howden et al. 2007).

Adaptation is not new. Australian farmers have always adapted to past changes in prices, technologies and climate variations as well as institutional factors (e.g. McKeon et al. 2004). The rationale for having a focus on adaptation to climate change is that the changes are likely to be far-reaching, systemic and to some extent, able to be foreseen, and so there is a case for advanced preparation. For example, the recent IPCC Fourth Assessment Report concludes that Australian agriculture and the natural resource base on which it depends has significant vulnerability to the changes in temperature and rainfall projected over the next decades to 100 years (Hennessy et al. 2007). Climate change will add to the existing, substantial pressures on Australia’s agricultural industries and will interact strongly with the food security challenge over the next decades: that is, to effectively double food production while reducing greenhouse gas emissions, reducing impact on biodiversity and the natural resource base while facing competition for land and water from urban encroachment and biofuel use. To be prepared for this challenge, we argue here that there is a need to start developing and implementing adaptation strategies now. This book is aimed at assisting such efforts.

Table 1.1: Major components of the climate system relevant to climatic variability and land management in Australia’s agricultural systems. The cited reference indicates examples of the influence of components on Australian rainfall, controlling climate systems and vegetation response (after Meinke and Stone 2005; McKeon et al. 2009).

Component of climate system variation	Time period	Literature cited
Madden-Julian Oscillation (MJO)	Intra-seasonal (30–60 days)	Donald et al. (2006)
Quasi-biennial Oscillation	2½ years	White et al. (2003)
El Niño-Southern Oscillation (ENSO)	Inter-annual (2–7 years)	Pittock (1975)
Southern Annular Mode (SAM)	Inter-annual and trends	Marshall (2003)
Indian Ocean Dipole (IOD)	Inter-annual and decadal	Saji et al. (1999)
Pacific Decadal Oscillation (PDO) or Inter-decadal Pacific Oscillation (IPO)	Inter-decadal	Power et al. (1999)
Multi-decadal	30–100 years	Hendy et al. (2003)
Global Warming and Greenhouse	Since late-1800s	Nicholls (2006)
Stratospheric Ozone Depletion	Since 1970s	Syktus (2005)
Asian Aerosols	Since 1980s	Cai and Cowan (2007)
Land Cover Change	Since mid-1800s	McAlpine et al. (2007)
Very Long-term Oscillations (e.g. Milankovitch cycles or Ice Ages)	Thousands of years	De Deckker et al. (1988)

The importance of developing effective strategies for adapting to climate change has been recognised by the governments of the Commonwealth, States and Territories. Initiatives such as the Garnaut Climate Change Review (http://www.garnautreview.org.au), the National Climate Change Adaptation Research Facility (www.nccarf.edu.au) and the CSIRO Climate Adaptation Flagship (www.csiro.au/org/ClimateAdaptationFlagship.html) are seeking to more fully understand the implications of climate change and the actions that could be taken to address this challenge. It is now recognised that in order to assess the costs (and benefits) of climate change, we need to include the costs (and benefits) of mitigation, the costs (and benefits) of impacts and the costs (and benefits) of adaptation (Howden et ...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Preface
• List Of Contributors
• 1: Introduction
• 2: Climate Projections
• 3: Grains
• 4: Cotton
• 5: Rice
• 6: Sugarcane
• 7: Winegrapes
• 8: Horticulture
• 9: Forestry
• 10: Broadacre Grazing
• 11: Intensive Livestock Industries
• 12: Water Resources
• 13: Marine Fisheries and Aquaculture
• 14: Agricultural Greenhouse Gases and Mitigation Options
• 15: Enhancing Adaptive Capacity
• 16: Summary
• 17: Looking Forward
• 18: Frequently Asked Questions
• Index