An Overview of Climate Change and Impacts on Food Security in Small Island Developing States

Introduction

Our climate is warming at a pace unparalleled in the history of our planet (Lobell & Burke, 2010; Stocker et al. 2013). We no longer have the luxury of pretending that climate change is not happening. Although some people may be skeptical, over 97% of climate scientists from around the world agree our climate is warming and changes observed over the last 100 years are attributable to activities by people (Anderegg et al. 2010; Doran & Zimmermann, 2009; Oreskes, 2004; Stocker et al. 2013). The Intergovernmental Panel on Climate Change (IPCC) reports that atmospheric greenhouse gas concentrations have increased, mean surface temperatures for land and oceans have warmed, sea levels have risen and snow and ice levels have decreased (Stocker et al. 2013). Globally, the last three decades have been the warmest recorded since 1850 (Figure 1). A failure to acknowledge these challenges and start planning is a recipe for disaster.

Figure 1.

Observed globally averaged combined land and ocean surface temperature anomaly 1850-2012 (© 2013, Intergovernmental Panel on Climate Change. Adapted from IPCC 2013: Summary for Policymakers. In Climate Change 2013: The Physical Science Basis. Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, Figure SPM 1. Used with permission.)

The impacts from climate change will be widespread and inequitably distributed around the world. Terrestrial areas along coasts and SIDS will be particularly vulnerable to impacts from climate change. Climate change will impact nations both large and small. Island territories from developed nations, like the U.S. Caribbean islands of the U.S. Virgin Islands and Puerto Rico, and the U.S. Pacific islands of Hawaii, Guam, the Northern Marianas Islands and American Samoa will face many of the same climate change challenges facing SIDS. The Japanese islands will also face some significant challenges. However, SIDS will be impacted by a unique set of challenges and responding to those challenges will stress finite resources in these small nations.

Climate Change Overview

Before beginning a discussion about climate change, it will be helpful to define what is meant by the term climate. Climate is weather observations averaged over long periods of time, typically 30-year periods (IPCC, 1995). In contrast, meteorology is the study of weather patterns in the short term. Humans have long made observations about weather. However, the use of accurate and reliable scientific instruments to capture direct data on weather at a global scale began in the mid-1800s and comprehensive data collection and analysis did not begin until the 1950’s (Stocker et al. 2013). Climate data from earlier periods is created using paleoclimate reconstructions. Paleoclimate reconstructions use a variety of proxies to substitute for actual weather measurements, such as ice cores, marine and lake sediment samples, coral samples, bore holes, tree rings and glacier length records (National Research Council, 2006). Combined, actual weather measurements and paleoclimate reconstructions provide scientists with a comprehensive picture of the Earth’s climate over time.

Climatologists can study climate at a variety of spatial and temporal scales. Spatial examinations can occur at local, regional, hemispheric and global scales. Temporal examinations can span decades to centuries to even millennia. Scientists understand that the Earth’s climate has always been variable, especially when examined at the local and regional levels across shorter periods of time (Stocker et al. 2013). Variations in climate are expected and can be attributed to natural phenomena like large volcanic eruptions, solar variations and subtle changes in the Earth’s orbit (National Research Council, 2006).