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Today coral reefs, perhaps more than other marine systems, are suffering from numerous pressures. As a result many have succumbed as functioning ecosystems. Nutrients and industrial pollution, shoreline alterations, diseases of corals and other important groups of organisms, and over-extraction of fish, invertebrates and even the limestone rock itself, have all contributed to the demise of about one third of the world's reefs. More recently, climate change, notably a rise in sea temperature which has led to coral bleaching and then death of component corals, has added to the stress imposed on this ecosystem. In future, ocean acidification, sea level rise and increased storms will add further stress. Many of these factors interact, making the precise responses of reefs to these changes very complex.

The ocean and the atmosphere exchange massive amounts of carbon dioxide (CO2). The pre-industrial influx from the ocean to the atmosphere was 70.6 Gt C yr –1 , while the flux in the opposite direction was 70 Gt C yr –1 ( IPCC 2007 ). Since the Industrial Revolution an anthropogenic flux has been superimposed on the natural flux. The concentration of CO2 in the atmosphere, which remained in the range of 172–300 parts per million by volume (ppmv) over the past 800 000 years ( Lüthi et al. 2008 ), has increased during the industrial era to reach 387 ppmv in 2009. The rate of increase was about 1.0% yr –1 in the 1990s and reached 3.4% yr –1 between 2000 and 2008 ( Le Quéré et al. 2009 ). Future levels of atmospheric CO2 mostly depend on socio-economic parameters, and may reach 1071 ppmv in the year 2100 ( Plattner et al. 2001 ), corresponding to a fourfold increase since 1750. As pointed out over 50 years ago, ‘human beings are now carrying out a large scale geophysical experiment of a kind that could not have happened in the past nor be reproduced in the future’ ( Revelle and Suess 1957 ). Anthropogenic CO2 has three fates. In the years 2000 to 2008, about 29% was absorbed by the terrestrial biosphere and 26% by the ocean, while the remaining 45% remained in the atmosphere ( Le Quéré et al. 2009 ). The accumulation of CO2 in the atmosphere increases the natural greenhouse effect and generates climate changes ( IPCC 2007 ). It is estimated that the surface waters of the oceans have taken up 118 Pg C, or about 25% of the carbon generated by human activities since 1800 ( Sabine et al. 2004 ). By taking CO2 away from the atmosphere, the oceanic and terrestrial sinks mitigate climatic changes. Should their efficiency decrease, more CO2 would remain in the atmosphere, generating larger climate perturbations. This book has four main groups of chapters.

Fossils potentially provide direct evidence on how changes in growth strategies may have affected diversification patterns in geologic time. New strategies may have allowed some species to exploit new ecological opportunities or contributed to their demise. This chapter discusses the following topics: ocean acidification in the past and today; major patterns of larval evolution in the oceans; climate change and mammalian developmental evolution; Jurassic sharks; survival and diversification in the early mammalian lineage; and islands as experiments in life history evolution.

This chapter examines the impact of the so-called “nuisance beavers” on the landscape. It argues that “nuisance beaver” is a misnomer, since damage to crops, tree plantations, roads, water supplies, and recreational facilities such as golf courses and campgrounds results from human encroachment on the beaver's habitat, not the other way around. It also considers how the beaver's recent spectacular expansion of its range southward from wilderness to developed land has intensified the conflict between humans and animals. It shows that the beaver causes economic losses by flooding and softening roads as well as flooding often tens of acres of farmland and golf courses. Finally, it asks whether the beaver can help in the fight against acid precipitation or contributes more to the acidification of many bodies of water.

What is the future for the planet, and for climate? Gazing into crystal balls is a pastime that humans have a fascination for. It is also one in which they have a dismal record. A generation or two ago, there were predictions of cities made of glass or plastic, clothes of aluminium or asbestos, flying cars, the fall of nationalism and the rise of world government, the demise of religion, and robots taking over our tasks and ushering in an age of universal leisure for all. So much for all that. When we move, then, to the almost limitless complexities and intersecting feedbacks of Earth’s climate system, one might be forgiven for throwing in the towel straight away. This is a system, we must eternally remember, of which we have only partial understanding, even as we see today’s weather patterns spin off from it. Go back into the deep past, and that climate and those long-vanished weather patterns leave only traces in strata that are, in large part, invisible to the naked eye. And of the future, of course, we have no samples, no deep boreholes, no fossils: the canvas is blank—indeed, as yet there is no canvas at all. Yet, from those ancient stratal traces we can construct a picture of events that is both vivid and (within our levels of uncertainty) true. There is no reasonable doubt that 20,000 years ago massive ice sheets spread out from the poles—or, that 125,000 years ago there was a climate on Earth as temperate, within a degree or so, as the one we enjoy today. So, there are patterns, real patterns that we can use as guides to help us try, with the utmost caution and scepticism, to create pictures, scenarios, sketches of the climate of the future. One might imagine alternative futures—or create them—particularly with the help of those elapsed realities. For instance, one might take that striking five-million year slice of climate history put together by Lorraine Lisiecki and Maureen Raymo (see Ch. 8 ).

Climate change will challenge the human community in many ways for centuries to come. Human influence on the climate is now the primary driver of the shift to a less stable and more dynamic global environmental system—the Anthropocene. In this chapter we explore some profound implications of this new age. First, what we mean by “the environment” is now itself ever-changing, with human actions affecting the very makeup, functioning, and evolution of global and local ecosystems, pushing them in new directions that can be difficult to predict. Second, this new reality has consequences for the founding principles of environmental management, conservation, ecosystem restoration, and action on the environment in general. The use of the past as a baseline natural world to be restored or mimicked is no longer possible, and so the era of preservation as the basis of environmental management is over. Climate change is pushing ecological systems out of their Holocene comfort zone (the last 10,000 years of unusual climatic stability). Our conceptions of a “natural” world and how people relate to it will have to change as well. Scientific controversies, environmental politics, and ecological management begin to look very different as a result. While most environmental scientists warn of the profound difficulties of navigating the Anthropocene, some technological optimists envisage a brave new future where humanity progresses through continued advances in biotechnology, information technology, and nanotechnology (Silver, 1997; Kurzweil, 2005). In this light, climate change and the transition to the Anthropocene are just a bump in the path of human progress. This kind of thinking extends to geo-engineering the planet to both avoid the worst of climate change and even push human development in new directions. While some climate scientists are beginning to explore the possibilities and consequences of geo-engineering, others are concerned that such bold action will exacerbate environmental uncertainties. These tensions among scientists represent competing visions of the degree to which governance informed by science can really understand and constructively guide Earth processes. If humanity survives into the long run, there may be ways that the Anthropocene can be organized to provide for both ecosystem and human functioning.

Rainbow Beach is a small town on the coastal dunes of eastern Australia, near Brisbane. I had travelled there to meet with some colleagues to sample soils from the vast coastal sand dunes that surround the area. It might seem an unusual place to visit to collect soil, but a unique sequence of soils has formed in the sand dunes, which differ greatly in age. As you move inland from the sea, the soils get progressively older and deeper, and more weathered and nutrient-poor. The youngest soils are shallow, having only just started to form in recent sand dunes, whereas the oldest soils are around half a million years old and can reach 25 metres deep. These are among the oldest, deepest, and most weathered soils that I have sampled, and what I recall most vividly is how stunted and sparse the vegetation was that grew there, reflecting their struggle to grow in such ancient, weathered soil. The soils of Rainbow Beach are by no means the oldest on Earth. Hidden beneath ice sheets in Greenland, scientists recently discovered a soil that was 2.7 million years old, a remnant of the fertile tundra that covered the area before the ice sheets came. And scientists working in South Africa recently discovered a soil, now compacted in rock, that is 3 billion years old. One of the most fascinating things about soil is that it is incredibly diverse; soils vary enormously across continents, countries, and from valley to valley and field to field. Even within a small patch of land, such as a field, forest, or vegetable garden, the underlying soil can vary considerably. Over distances of metres, it might differ in its texture and depth, and in its pH, being acid in one patch of a field and neutral in another. Soils also vary greatly in the diversity of living organisms that live within them. I will go into more detail about the diversity of soil life later in this book; but for now suffice to say that it is vast. Soils also change with time.

This chapter reviews the current state of knowledge about the diversity in physiological responses (including energy metabolism, acid–base balance, and biomineralization) to ocean acidification (OA) in four major taxonomic groups of marine calcifiers—corals, molluscs, crustaceans, and echinoderms. The interactive effects between acidification and other commonly occurring environmental factors, such as temperature, salinity, hypoxia, and trace metals, on the physiology of these animal calcifiers is reviewed. Assessment of the inter-phylum and inter-species variability in response of OA (either alone or in combination with other stressors) is critical in identifying most vulnerable ecosystems as a focus for conservation efforts, reducing the impact of other stressors such as pollution, and aquaculture efforts to improve resilience of existing stocks of economically important marine organisms.

Climate change presents a particularly tough challenge. There are of course plenty of other tough problems around: inequality, poverty, terrorism, the instabilities of financial systems, the risks of nuclear technologies, persistent and potentially violent antagonisms in international politics. Yet we have at least a sense of the nature of these sorts of problems, and governments know more or less how to respond to them, although they do not always do so—or do so successfully. The challenges of climate change, by contrast, almost seem to defy comprehension, let alone appropriate response. The science is complex and long contested by a well-financed movement that accuses climate scientists of falsifying conclusions in support of a left-wing political agenda. There is a collision between what the science implies and seemingly common-sense understandings based on casual observation of the weather. The size of the threat calls into question received ideas about the inevitability of human progress: if progress requires continued economic growth based on ever-increasing emissions of greenhouse gases, then that kind of progress is clearly no longer sustainable. The economic stakes could not be higher, calling into question the future of industries such as coal and cars, and leading to deep political conflicts as those whose industries, profits, employment, and lifestyles feel threatened resist the necessary changes. Even among those who accept the science and recognize the size of the challenge, key questions are hotly debated. So there is dispute about how to think of the risks that climate change brings: for example, should we spend money on preparing for low-probability but potentially catastrophic impacts (such as rapid sea-level rise)? To what extent should we care about the risks our current emissions are imposing on future generations, who will suffer the impacts? If it is accepted that emissions need to be reduced, how rapidly should that reduction occur in light of the economic costs that it will necessarily impose? And how should the burden of reductions be allocated between rich and poor countries, between rich and poor people within countries, between different industries and economic sectors?

Understanding lake chemistry is critical for correctly interpreting the geochemical archives of lake deposits. Elemental and isotopic distributions in lakes are closely linked to external climatic and watershed processes. Solute concentrations regulate the distribution of organisms, and the precipitation or dissolution of mineral phases. Both fossils and minerals leave sedimentary archives, and when we can interpret aspects of ancient water chemistry from these records we may be able to reconstruct paleoclimate or prior human activity around the lake. Interpretation of isotopic records likewise requires an initial understanding of their behavior in lakes and the links between this behavior and external factors such as rainfall or nutrient discharge. Oxygen (O2) is the second most abundant component of the atmosphere (∼ 21%) after nitrogen (∼ 78%): Paleolimnological indicators of oxygenation at the sediment–water interface may provide clues as to the nature and frequency of water-column mixing, water depth, the lake’s trophic condition, and possibly climate. Thus, it is important to understand how oxygen is generated and consumed in lakes to properly interpret the oxygenation archives and filters. Oxygen is dissolved in lakes directly from air, and as a byproduct of photosynthesis by autotrophic organisms (multicellular plants, algae, and photosynthetic bacteria), greatly simplified as: . . . 6CO2 + 6H2O + sunlight → C6H12O6 + 6O2 (4:1) . . . Photosynthesis is performed by both organisms on the lake floor (phytobenthos), and by floating algae and bacteria (phytoplankton). Molecular oxygen is lost from the water column through respiration, secondary oxidation of organic or inorganic compounds in the water column or sediments, or directly to the atmosphere following supersaturation. Oxygen concentrations in the water column are a function of productivity, respiration, temperature, and mixing, all of which vary both diurnally and seasonally within a lake, and because of climatic or morphometric differences between lakes. To understand this variation, it is useful to return to our examples at Junius Ponds #5 and #7. In dimictic Junius Pond #7, the water column just below the ice is well oxygenated during the winter, but is anoxic at the lake floor.

This chapter lists the natural and manmade causes of frog malformations. The natural causes of malformations include wounds from failed predation attempts, fish excrement, extreme tadpole densities, lathyrogens, nutritional deficiencies, ultraviolet-B radiation, diseases, temperature, hereditary factors, and parasites. Several manmade causes of amphibian malformations include acidification, radioactive pollution, ozone depletion, heavy metals, retinoids, agricultural chemicals, and xenobiotics. The chapter also discusses the correlation between morphology and cause of malformation type.

This chapter details the development of the regional air pollution information and simulation model (RAINS) in 1984, a project which has been retrospectively described as one of the highest achievements of IIASA, substantiating East-West collaboration beyond scientific diplomacy. RAINS consisted of three blocs: pollution generation, atmospheric processes, and environmental impact, with further submodels to investigate emissions, long-range transport, and acidification. The model was interactive: a policy maker could select a particular national pathway of energy use, a strategy of pollution control, and environmental impact indicators. On the basis of this information, the computer model simulated the interaction of these three systems, enabling the user to examine the consequences of different alternatives to control acidification.

Disturbances disrupt ecosystem processes, thereby affecting the distribution and abundance of biota. Disturbances alter light and temperature regimes, carbon dioxide and nutrient fluxes, and productivity. The disturbance of one ecosystem factor is likely to affect most others, as biogeochemical cycles are coupled — to each other and also to landscape and anthropogenic factors. This chapter addresses how organisms respond to alterations of ecosystem processes in the air, soil, and water. Specifically, how do disturbances alter terrestrial light levels, air temperature, carbon dioxide levels, soil nutrients, soil pH, and soil organisms? In aquatic habitats, how do disturbances alter nutrient fluxes, enrichment, and acidification? In addition, transfers of energy and matter across interfaces of aerial, terrestrial, and aqueous parts of an ecosystem are covered. The responses of productivity to disturbance are also examined.

In the face of concerted opposition to reducing fossil fuel emissions from industry, ideas about the importance of obtaining scientific evidence of environmental harm underwent a significant shift in the mid-1980s. Coal industry representatives continued to claim that expensive pollution controls should not be installed while the science of acid rain was still "uncertain." Yet the potentially serious environmental risks of doing nothing continued to grow, as West German scientists found evidence that their country might also be experiencing the effects of acid rain. Rather than continue to debate whether scientists had obtained sufficient proof of the dangers from fossil fuels, European regulators instead began developing the idea of a precautionary approach to pollution policies. The precautionary principle, as they redefined it, gave them a way to act with “uncertain” knowledge and undercut the ability of industry to further delay the imposition of regulations. Under pressure from the European Communities, Britain's coal industry tried to buy themselves more time before needing to implement expensive control technology through a scientific "bribe" to Scandinavian scientists. But despite their efforts, the British government ultimately acceded to demands from the European Communities to reduce air pollution from their coal industry.

This chapter provides an overview of the challenges that Ocean and Coastal Law faces in responding to climate change impacts. First, it describes the geological history of climate change and explains the mechanisms behind the recent anthropogenic alterations in the Earth’s climate precipitated by fossil fuel emissions. Second, it discusses the impacts of these changes on ocean acidification, stratification, thermal expansion, shifting atmospheric cells, tropical cyclone activity, and saltwater intrusion into coastal freshwater. The chapter reviews the impacts of temperature on a variety of scales from cellular, organism, population, and ecosystem level using species-specific case studies. It also examines information on the impacts and potential impacts of temperature change on major coastal habitats such as seagrass, coral reefs, and mangroves. The chapter concludes with an assessment of trends in climate change impacts on marine resources by region.