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International assessments of ozone depletion began in the 1980s, after anti-regulation groups (such as the CFC industry) seized on differences between early national and institutional assessments, and the policy leanings expressed in some of them, as justification to delay regulation of CFCs. This spurred Bob Watson and colleagues to bring together scientists of varying nationalities, disciplines, and interests to produce large international ozone assessments, with the explicit goal of being seen as authoritative, credible, objective, and policy-relevant but not policy-prescriptive. These scientists focused on producing brief, accessible executive summaries, replete with neutrally phrased if–then statements, thought to appeal to busy politicians. These assessments are widely regarded as very successful, most importantly for having contributed to the Montreal Protocol. However, when unexpected seasonally and geographically localized ozone depletion was detected over Antarctica (the Ozone Hole), assessors faced huge uncertainty and insufficient understanding of heterogeneous chemistry, which had formerly been dismissed as unimportant. In response they produced new knowledge by repurposing ozone metrics such as chlorine loading potential to predict future ozone levels in the absence of adequate models. The assessment of ozone depletion illustrates how an assessment may be highly successful even while grappling with highly uncertain scientific knowledge.

Ultraviolet B radiation (UVBR, 280–320 nm), the most biologically damaging portion of the solar spectra reaching the Earth’s ground, received considerable scientific attention after the discovery of the spring stratospheric ‘ozone hole’ formation in the late 1970s over Antarctica. Recently, similar low ozone conditions were observed over the Arctic and occasionally at lower latitudes. Furthermore, expected ocean acidification, increased surface water temperatures, and modifications in the structure of the water column due to global change expanded the concerns regarding the potential damage of global change to the structure of marine food webs. This chapter reviews the effects of UVBR on various marine ecosystems. Introduction of the chapter gives a description of factors that influence the UVBR intensities that reach these ecosystems such as latitude, season, stratospheric ozone layer thickness, and penetration within the water column. Then, the chapter depicts the effects of UVBR on the food webs of some important marine ecosystems, such as polar oceans, coastal waters, fronts and upwellings, oceanic gyres, and benthic ecosystems including coral reefs. Finally, this chapter investigates the potential interactions of enhanced UVBR along with other climate change stressors such as global warming and ocean acidification.

The international effort to protect the stratospheric ozone layer successfully integrated science and technology into international environmental diplomacy and solved a global environmental problem. Research scientists identified the problem and its cause, winning a Nobel Prize for their efforts. Opponents of government regulation attacked their findings, but their campaign fell flat. An epistemic community educated governments and convinced them that international action was needed to protect people from skin cancer and to shield ocean ecosystems from disruption. Manufacturers promised to stop producing ozone-destroying chemicals (chlorofluorocarbons [CFCs]) if they were proven to harm human health. Despite lingering scientific uncertainty, governments agreed in the Montreal Protocol to tentative measures to limit CFC production and sale. Once the science was well established, governments agreed to more comprehensive measures, including regular briefings on scientific and technological developments. This approach, however, has had less success when applied to the more difficult problem of climate change.

In this conversation, Nobel Prize winner Mario J. Molina reflects on the ethical side of science. He explains how several decades ago, together with the scientist F. Sherwood Rowland, he predicted that human activity was endangering the ozone layer. They discovered the mechanisms which could bring about the destruction of the layer due to the continuous release of industrial compounds, such as the so-called chlorofluorocarbons (CFCs), into the atmosphere. Professor Molina relates how the issue with the ozone layer was the first example of a problem on a truly global scale for science and, as such, had to be tackled, because without the ozone layer, life on our planet would not have evolved as we know it. Education and training are proving a great help with how the present challenge of stopping or mitigating the daunting problem of global warming should be approached. In the dialogue, different courses of action for persuading both decision-makers and the public are proposed. It is however proving rather difficult to achieve and something which, according to Professor Molina, is also related to education.

The importance of ozone to life on Earth and to atmospheric chemistry cannot be overstated. Nucleic acids and other macromolecules essential to life absorb strongly in the ultraviolet (UV) and are damaged by UV radiation with wavelengths of less than approximately 300 nm. For proper functioning, such biological macromolecules need to be shielded from the full intensity of solar radiation. Molecular oxygen (O2) absorbs strongly and blocks solar radiation with wavelengths below 230–240 nm from reaching the Earth’s surface. However, oxygen is transparent at wavelengths above approximately 245 nm. Fortunately, absorption of UV radiation of wavelengths of less than 242 nm by molecular oxygen (O2) yields oxygen atoms that add to O2 to form ozone which has a very strong absorption band at 200–300 nm. Even though it is present in only trace amounts in the atmosphere, absorption by ozone effectively blocks harsh solar UV radiation from reaching the Earth’s surface. There is no other molecule in the atmosphere that provides protection from solar UV radiation in the 250–300 nm region. The development of the ozone layer is intimately connected to the development of life on Earth. Oxygen levels in the prebiotic atmosphere were less than 5 ×10−9 of the current level. Photosynthesis after the appearance of life on the planet more than 3.5 billion years ago led to increased oxygen levels in the atmosphere. By approximately 600 million years ago, the O2 concentration had exceeded 10% of the current level, and the corresponding layer of ozone was sufficient to offer an effective UV shield for the migration of life onto land (Wayne, 1991). Life on Earth as we know it would not have developed without the protection offered by the ozone layer, and, equally, the ozone layer would not have developed without life on Earth. In addition to its obviously important physical role in shielding biota from the damaging effects of harsh UV radiation, ozone plays an essential chemical role as a photolytic source for HO radicals.

There was a time when the primary concerns of the product engineers were the needs of the buyers and consumers of their products, and they concentrated most of their efforts on design and manufacture of products with the goal of meeting their requirements and approval. A product will certainly fail if it does not have the steady and continued confidence of the consumers. The CPI, just like any other industry at that time, were accountable mostly to the consumers. This was a two-party transaction, where the buyer gave the seller money in return for a satisfactory product. This form of two-party transaction is no longer valid, as there are many bystanders whose welfare can be damaged in the transaction and their welfare must also be safeguarded. The manufacturing and marketing of chemical products is now a multiparty transaction, as the public and the governments have forcefully placed themselves into part of the bargain. The product engineers must become cradle-to-grave stewards of their products, and must solve many safety and environmental problems: from the extraction of raw material from farms and mines, to transportation on land and over water, to manufacturing in plants, to use in the customers hands, and finally to recycle back to nature. Before you begin to design the product, you need to focus your attention on the customer and their needs, but you also need to focus your attention on the potential hazards that the product poses to the safety and health of your workforces and the neighbors, and to the environment. You need some familiarity with the history of past mistakes, with the current government regulations, and with methods to deal with these potential problems. Over a long period of history, commercial transactions were primarily a two-party affair, between the seller and the buyer. In the last few decades, a third party has forcefully entered into the transaction, based on concerns about safety and the environment, and on public opinion and government regulations. This is shown in figure 10.1.

This chapter gives a description of the main characteristics of present-day climate. In describing the mean state and its variability, attention is also given to the underlying causes. For comparison, there is a short summary of early European climate, from the last glacial maximum, through the Holocene and up to the Little Ice Age (the period AD 1400–1850). The chapter finishes with a comprehensive section on climate change, with emphasis on the anthropogenic causes of recent changes. The climate of western Europe has a maritime character. The weather mainly originates from the North Atlantic Ocean and its neighbouring seas. Further inland, in what is usually called central Europe, climate changes to a more continental type, but certain maritime features are still present. It is therefore called an altered maritime climate. Only in the most southern part, southern France for instance, is the Atlantic character lost and several new features are present. These features are characteristic of a Mediterranean climate. Climates may be called cold or warm, dry or wet, gloomy or sunny, depending on the prevailing temperatures, amount and frequency of precipitation, and the number of hours of bright sunshine. Such terms, however, are not objective unless certain, generally accepted, reference values are used. In the past different sets of reference values were proposed, each of them defining a system of climatic types. A well-known classification system was the one developed by Köppen (1936). The Köppen system distinguished eleven main climate types, based on well-defined temperature and precipitation characteristics. These were mainly referring to the response of vegetation, natural as well as cultivated, to climatic conditions. The eleven Köppen climates are indicated by the letters A–E, with some subdivision, using other letters. In the Köppen classification the whole of western Europe has a Cf climate, which means a moist, temperate climate, without a specific dry season. Cf climates occupy 22% of the globe (oceans included). A second method to describe climate is by using the well-known definition of climate as being the average weather conditions in a certain area, over a given period of time. In practice, however, there is no direct information about weather conditions.

By the mid-1980s, as the nation confronted new problems such as the ozone hole and long-standing issues such as acid rain, the Environmental Protection Agency (EPA) faced reduced political support for direct mandate interventions. Harnessing growing support for market-based strategies among environmental advocates, the EPA increasingly turned to incentives, tradable allowances, and other market-based policies in the 1980s. This shift culminated in the development of the nation’s first cap-and-trade program to address the problem of acid rain in the Clean Air Act Amendments of 1990. As the nation looked forward to new concerns including global warming, an era of direct mandates informed by natural rights to clean air and a healthy environment seemed to be at a close, supplanted by a new environmentalism that held out market-based policies and a monetary conceptualization of environmental value as a new model for governance.