Hannah, L.2014. Climate Change Biology. Academic Press, ISBN 978‐0‐124‐20218‐4. 470 pp, $101 (Hardback)

Abstract

Since Aristotle, science, and biology in particular, has become fractionated into many disciplines, which have been further subdivided into specialities as formalisms and concepts have diverged progressively. As a result, communication between scientists has become more and more difficult. Although science specialization reflects our increasing scientific knowledge, fractionation due to specialization has become a serious issue now that our planet is under global pressure. Lee Hannah has written a thorough introduction to climate change biology. This book presents all scientific fields needed to understand the implications of climate change on biological and ecological systems in a very comprehensive way. The book is well illustrated with key color graphics. The book has six main parts: (1) an introduction where the author presents briefly the new field of climate change biology and present a rapid introduction to the climatic system and climate change; (2) a part devoted to the current influence of climate change on both biological and ecological systems; (3) a part that examines past effects of climate change on species and ecosystems; (4) a part that examines how climate change may affect biology, explaining the methods designed and applied by scientists to anticipate the effects of climate change; (5) Implications for conservation are thoroughly examined and the authors provide some clues about species adaptation to climate change; (6) The last part is about climate change mitigation. In the first part, the author reminds us that climate has always fluctuated in a myriad of time scales and that there are many drivers of climate change (e.g., volcanoes, solar forcing, etc.). Nevertheless, evidence is presented that current climate change might be anthropogenic, exceptionally rapid and strong. Chapter 2, introducing the field of both fundamental and applied climatology, summarizes key arguments advanced by climatologists to explain why current climate change is singular and how and why it might influence the functional units (e.g., cryosphere, oceanic, and terrestrial biosphere) of the Earth system. Quite interesting points are the distinction of different types of global models, the description of different techniques of downscaling, velocity of climate change, stable states and the ephemeral nature of communities. For beginners, this is an excellent introduction to the field. In the second part, the author presents biogeographical and phenological shifts as well as ecosystem changes. In the three chapters, the author describes patterns of changes and explains mechanisms and proximate causes. The author shows that even if climate is the trigger of many spatial and temporal changes in species abundance, proximate causes often involve species interactions (e.g., Arctic fox, quetzal, pied flycatchers, lodgepole pine). Examples from the marine and terrestrial realms are judiciously chosen and there is no geographical bias. The author shows that life can be affected by climate change not only by the effect of long-term temperature changes but also by the effects of water availability (e.g., drought); the production of flowers, seeds, and fruits are controlled by temperature and water availability. The potential influences of extreme events are also developed. In the third part, the author emphasizes that “the lesson of the past is that when climate changes, species move.” This is an important point, too many researchers still think that species can quickly (within a few centuries) adapt to climate change. Although some species may eventually adapt, this will not be the case for most species (Crisp et al. 2009), especially if climate change is rapid and strong. The author investigates the implications of climate change at time scales ranging from the tectonic to the millennial time scales, covering the last 90 million years, the Pleistocene, relatively well-documented episodes of rapid climate change (e.g., the Younger Dryas and Dansgaard-Oeschger events). Effects of past changes on marine ecosystems such as shifts in temperature, sea-level, ocean circulation, ocean chemistry, and turbidity are reviewed. Chapter 9, devoted to extinction, is quite interesting. The author develops the causes and consequences of the five major extinctions of the Phanerozoic Eon and shows that even if climate change was not the trigger of all extinctions, they all involved climate change. The fourth part reviews in depth what could be the implications of climate change on biological and ecological systems and their potential implications for ecosystem services. Empirical investigations from laboratory and field experiments are reviewed for both marine and terrestrial ecosystems. Physiologic theory is also briefly mentioned. I think this is an important point as we have in the field of climate change biology many theories and empirical generalizations that could be helpful for anticipating the implications of climate change on species and ecosystems. Modeling the implications of climate change is well presented and the author describes both conceptual and mathematical models. Lee Hannah reviews advantages and limitations of three types of models: (1) phenomenological (species distribution and ecological niche) models, (2) mechanistic models (dynamic global vegetation) models, and (3) gap models. In addition, earth system models, combining biological and climatic processes and resulting from the joint use of a GCM and a mechanistic model for the terrestrial and the marine biospheres are introduced. Extinction risks of species from climate change are evaluated and recent estimations climate-induced extinction are explained. Limitations of an early study led by Thomas et al. (2004) are well described and the author, who was also involved in this study, explains why investigations of past extinctions should be used with caution to anticipate future effects. The implications of climate-induced biodiversity changes for ecosystem services are reviewed. In the marine environment, it is shown that although fish are being replaced by more thermophile species in temperate and polar systems, tropical fish biodiversity is decreasing because the disappearance of the less thermophile species is not compensated, a result predicted from ecological theory. Other consequences such as coastal erosion, carbon sequestration, water provisioning, fire, and water supply are explored. The fifth part estimates the implications of climate change in term of conservation and both species and ecosystem management. The author stresses that although species may move out of protected reserves; others may also invade them and become protected. Lee Hannah also emphasizes the point that leading edge has been more investigated than rearing edge, although ecological theory such as the MacroEcological Theory on the arrangement of Life (METAL) theory clearly shows that they are both equally important (Beaugrand et al. 2014). Connectivity is an important issue in term of climate change. Chapter 15 details how connectivity can be achieved for area-demanding species (e.g., mammals), migratory species (e.g., birds), and for species that may exhibit large biogeographic shifts. This is a difficult task (1) because landscapes are strongly and directly affected by human activities and because (2) climate change may also affect the spatial distribution of human influence (e.g., shift in agriculture). The next chapter investigates how an improved management of species and ecosystems may mitigate climate change impacts. Solutions range from removing other stressors, assisted migration, targeted management, and habitat manipulation. The question of the cost of such an intensive management is also mentioned. Sadly, it seems that ecologists are anticipating the fact that greenhouse gas emissions will continue to rise and that climate change may become substantial because nothing is seriously done at the moment to mitigate anthropogenic causes of global climate change. The final part of the book is devoted to the issue of climate change mitigation. Starting from the United Nations Framework Convention on Climate Change (UNFCCC) agreed in Rio de Janeiro in 1992, Chapter 17 explains the work of the Intergovernmental Panel of Climate Change (IPCC), the Kyoto Protocol, the Carbon market and the issue of adaptation of people to the effects of climate change. Lee Hannah mentions a study of the World Bank that stresses that adaptation may cost between 70 and 100 billion of US $per year for a 2°C increase in global temperature. Chapter 18 is based on the review of Pacala and Socolow published in Science in 2004 (Pacala and Socolow 2004). This quite interesting chapter shows that it may be quite complex at the moment for human society to limit global warming under 2°C and that this can only be achieved by employing a variety of small mitigation solutions: e.g., more efficient car and building, use of renewable energy sources (e.g., photovoltaic cells and solar thermal energy, wind energy), biofuels and nuclear energy; the last two solutions have both advantages and limitations. The author also explains why climatic negotiations are so difficult; indeed although some countries will be strongly negatively affected by global climate change, others are likely to benefit from it. The last chapter is about carbon sinks and sources. The location of this chapter, which may seem more appropriated in the part devoted to the implications of climate change on ecosystem services, is understood when the section devoted to carbon sequestration is read. This book is an excellent primer to the field of climate change biology. The author presents in a comprehensive way this new field of applied ecology with key illustrations and shows the complexity of pathways by which climate change may alter the biosphere and how this may alter regulating and provisioning services. Lee Hannah offers us a trip back in time to better understand the relationships between climate and the biology and presents procedures and methods used currently to evaluate and anticipate the implications of climate change on species and ecosystems. Conservation issues are important and the socioeconomic aspect of climate change is outlined. Gregory Beaugrand, CNRS, Laboratoire d'Océanologie et de Géosciences UMR LOG CNRS 8187, Université des Sciences et Technologies Lille 1, BP 80, 62930 Wimereux, France; Gregory. Beaugrand@univ-lille1.fr