Global Warming

Regional patterns of climate change

So far we have been presenting global climate change in terms of likely increases in global average surface temperature that provide a useful overall indicator of the magnitude of climate change. In terms of regional implications, however, a global average conveys rather little information. What is required is spatial detail. It is in the regional or local changes that the effects and impacts of global climate change will be felt. Figure 6.6 Projected pattern average of surface temperature...

How stable has past climate been

Last Dryas Period

The major climate changes considered so far in this chapter have taken place relatively slowly. The growth and recession of the large polar ice-sheets between the ice ages and the intervening warmer interglacial periods have taken on average many thousands of years. However, the ice core records such as those in Figures 4.6 and 4.8 show evidence of large and relatively rapid fluctuations. Ice cores from Greenland provide more detailed evidence of these than those from Antarctica. This is...

The impact of climate change on fresh water resources

Fresh Climate

The availability of fresh water will be substantially changed in a world affected by global warming. Although uncertainties remain for projections of precipitation particularly on the regional or even river-basin scale, it is possible to identify many areas where substantial increases or decreases are likely Figure 6.7 . For instance, precipitation is expected to increase in high latitudes and in parts of the tropics and decrease in many mid latitude and sub-tropical regions especially in...

Modelling the weather

An English mathematician, Lewis Fry Richardson, set up the first numerical model of the weather. During his spare moments while working for the Friends' Ambulance Unit (he was a Quaker) in France during the First World War he carried out the first numerical weather forecast. With much painstaking calculation with his slide rule, he solved the appropriate equations and produced a six-hour forecast. It took him six months - and then it was not a very good result. But his basic methods, described...

Particles in the atmosphere

Small particles suspended in the atmosphere (often known as aerosol see Glossary) affect its energy balance because they both absorb radiation from the Sun and scatter it back to space. We can easily see the effect of this on a bright day in the summer with a light wind when downwind of an industrial area. Although no cloud appears to be present, the Sun appears hazy. We call it 'industrial haze'. Under these conditions a significant proportion of the sunlight incident at the top of the...

The IPCC Assessments

Nobel Paz 2007 Ipcc

Because of the scientific uncertainty, it has been necessary to make a large effort to achieve the best assessment of present knowledge and to express it as clearly as possible. For these reasons the IPCC was set up jointly by two United Nations' bodies, the World Meteorological Organization (WMO) and the United Nations Environmental Programme (UNEP).3 The IPCC's first meeting in November 1988 was timely it was held just as strong political interest in global climate change was beginning to...

What we can learn from carbon isotopes

Images And Carbon Isotopes

Isotopes are chemically identical forms of the same element but with different atomic weights. Three isotopes of carbon are important in studies of the carbon cycle the most abundant isotope 12C which makes up 98.9 of ordinary carbon, 13C present at about 1.1 and the radioactive isotope 14C which is present only in very small quantities. About 10 kg of 14C is produced in the atmosphere each year by the action of particle radiation from the Sun half of this will decay into nitrogen over a period...

Increasing human use of fresh water resources

Global Warming Fresh Water

The global water cycle is a fundamental component of the climate system. Water is cycled between the oceans, the atmosphere and the land surface Figure 7.5 . Through evaporation and condensation it provides the main means whereby energy is transferred to the atmosphere and within it. Water is essential to all forms of life the main reason for the wide range of life forms, both plant and animal, on the Earth is the extremely wide range of variation in the availability of water. In wet tropical...

Carbon trading

Carbon trading is an innovative market-based solution to the problem of reducing greenhouse gas emissions3. Its main rationale is that, by attaching a price to carbon dioxide emissions, trading schemes will generate powerful economic incentives to cut emissions and channel investment efficiently. Emissions trading works by setting limits on total allowable emissions that are then converted into tradable permits to be distributed amongst participants. For example, a company with commitments to...

Narrowing the uncertainty

A key question constantly asked by policymakers is 'How long will it be before scientists are more certain about the projections of likely climate change, in particular concerning the regional and local detail ' They were asking that question 20 years ago and then I generally replied that in 10 to 15 years we would know a lot more. As we have already seen, there is now more confidence that anthropogenic climate change has been detected and more confidence too in climate change projections than...

The photovoltaic solar cell

The silicon photovoltaic (PV) solar cell51 consists of a thin slice of silicon into which appropriate impurities have been introduced to create what is known as a p-n junction. The most efficient cells are sophisticated constructions using crystalline silicon as the basic material they possess efficiencies for conversion of solar energy into electricity typically of 15 to 20 experimental cells have been produced with efficiencies well over 20 . Single crystal silicon is less convenient for mass...

Example of a ZED Zero Emission fossilfuel Development

BedZED (Figure 11.8) is a mixed development urban village constructed on a brownfield wasteland in the London Borough of Sutton, providing 82 dwellings in a mixture of apartments, maisonettes and town houses together with some work office space and community facilities.22 The combination of super-insulation, a wind-driven ventilation system incorporating heat recovery, and passive solar gain stored within each unit in thermally massive floors and walls reduces the energy needs so that a 135 kW...

Sensitivity adaptive capacity and vulnerability some definitions

Sensitivity is the degree to which a system is affected, either adversely or beneficially, by climate-related stimuli. These encompass all the elements of climate change, including mean climate characteristics, climate variability, and the frequency and magnitude of extremes. This may be direct (e.g. a change in crop yield in response to a change in the mean, range or variability of temperature) or indirect (e.g. damage caused by an increase in the frequency of coastal flooding due to sea level...

Estimates of impacts costs under businessasusual BAU from the Stern Review

Using the PAGE 2002 Integrated Assessment Model (IAM),75 the Stern Review considers estimates of cost to the world's economies over the next two centuries if emissions of greenhouse gases continue on a 'business-as-usual' (BAU) path taking global average temperature increases possibly to 4 C by 2100 (cf. Figure 6.4) and 8 C by 2200. It is pointed out that modelling over many decades, regions and possible outcomes demands that distributional and ethical judgements are made systematically and...

The choice of stabilisation level

The last few sections have addressed the main greenhouse gases and how their concentrations might be stabilised. To decide how appropriate stabilisation levels should be chosen as targets for the future we look to the guidance provided by the Climate Convention Objective (see box on pages 291-2), which states that the levels and timescales for their achievement should be such that dangerous interference with the climate system is avoided, that ecosystems are able to adapt naturally, that food...

The impact on ecosystems

A little over 10 of the world's land area is under cultivation - that was the area addressed in the last section. The rest is to a greater or lesser extent unman-aged by humans. In Figure 7.13 are illustrated the world's major ecosystems (or biomes) with their global areal extent showing how they have been transformed by land use. Ecosystems are of great importance to human communities. They provide supplies for human communities in the provision of food, water, fuel, wood and biodiversity....

Sustainable development

So much for uncertainty in the science of global warming. But how does this uncertainty map on to the world of political decision-making A key idea is that of sustainable development. One of the remarkable movements of the last few years is the way in which problems of the global environment have moved up the political agenda. In her speech at the opening in 1990 of the Hadley Centre at the United Kingdom Meteorological Office, Margaret Thatcher, the former British Prime Minister, explained our...

The goal of environmental stewardship

Early in this chapter I invited you to imagine a voyage on Spaceship Earth. Let me leave you with two further metaphors to provide some perspective on sus-tainability especially as it is seen from the rich developed world. The first metaphor represents unsustainability I owe it to Professor Bob Goudzwaard20 of the Free University of Amsterdam. He asks us to imagine our position in the developed world to be like that of a passenger in a comfortable seat on a high-speed train - a train a grande...

Validation of the model

In discussing various aspects of modelling we have already indicated how some validation of the components of climate models may be carried out.17 The successful predictions of weather forecasting models provide validation of important aspects of the atmospheric component, as do the simulations mentioned earlier in the chapter of the connections between sea surface temperature For climate change over periods up to a decade, only the upper layers of the ocean have any substantial interaction...

The last thousand years

The detailed systematic record of weather parameters such as temperature, rainfall, cloudiness and the like presented above, covering a good proportion of the globe over the last 140 years, is not available for earlier periods. Further back, the record is more sparse and doubt arises over the consistency of the instruments Figure 4.5 Northern hemisphere temperature anomalies (relative to the 1961-90 mean) during the last 1300 years from ten published overlapping reconstructions from proxy...

Other factors that might influence climate change

So far climate change due to human activities has been considered. Are there other factors, external to the climate system, which might induce change Chapter 4 showed that it was variations in the incoming solar energy as a result of changes in the Earth's orbit that triggered the ice ages and the major climate changes of the past. These variations are, of course, still going on what influence are they having now Over the past 10 000 years, because of these orbital changes, the solar radiation...

Feedbacks in the climate system

Bilder Als Vollbild Darstellen

A Saharan dust storm originating in Mali blew off the west coast of Africa on 6 June 2006. Although partially hidden by the dust storm, the differences of the underlying landscape are still apparent as the sands of the Sahara give way to vegetation of the south. The Sahel is particularly vulnerable to desertification - land degradation from climate change and or human activity that transforms a region to a desert. increase, the actual rise in global average temperature was likely to be more...

Sir John Houghton

Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, Sao Paulo The Edinburgh Building, Cambridge CB2 8RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title www.cambridge.org 9780521882569 J. T. Houghton 1994, 1997, 2004, 2009 This publication is in copyright. Subject to statutory exception and to the provision of relevant collective licensing agreements, no reproduction of any part may take place without the...

Desertification

Drylands (defined as those areas where precipitation is low and where rainfall typically consists of small, erratic, short, high-intensity storms) cover about 40 of the total land area of the world and support over one-fifth of the world's population. Figure 7.10 shows how these arid areas are distributed over the continents. Desertification in these drylands is the degradation of land brought about by climate variations or human activities that have led to decreased vegetation, reduction of...

Forestclimate interactions and feedbacks

Various interactions and feedbacks are in play between forests and climate. Extensive changes in the area of forests due to deforestation can seriously affect the climate in the region of change. Changes in carbon dioxide, temperature or rainfall associated with climate change can have a major impact on the health or structure of forests that can in turn feed back on the climate. We consider some of these effects in turn. Changes in land use such as those brought about by deforestation can...

Regional climate modelling

The simulations we have so far described in this chapter are with global circulation models (GCM) that typically possess a horizontal resolution (grid size) of 200 or 300 km - the size being limited primarily by the availability of computer power. Weather and climate on scales large compared with the grid size are described reasonably well. However, at scales comparable with the grid size, described as the regional scale,29 the results from global models possess serious limitations. The effects...

The greenhouse gases

Industrial activity a source of carbon dioxide and other gaseous and particulate pollution. Industrial activity a source of carbon dioxide and other gaseous and particulate pollution. THE GREENHOUSE gases are those gases in the atmosphere which, by absorbing thermal radiation emitted by the Earth's surface, have a blanketing effect upon it. The most important of the greenhouse gases is water vapour, but its amount in the atmosphere is not changing directly because of human activities. The...

The challenge to all sections of community

In facing the challenge, it is important to recognise that the problems raised by global warming are not only global but long term the timescales of climate change, of major infrastructure change in energy generation or transport or of major changes in programmes such as forestry are of the order of several decades. The programme of action must therefore be seen as both urgent and evolving, based on continuing scientific, technical and economic assessments. As the IPCC 1995 Report states, 'The...

Thermal expansion of the oceans

Ocean Thermal Expansion

A large component of sea level rise is due to thermal expansion of the oceans. Calculation of the precise amount of expansion is complex because it depends critically on the water temperature. For cold water the expansion for a given change of temperature is small. The maximum density of sea water occurs at temperatures close to 0 C for a small temperature rise at a temperature close to 0 C, therefore, the expansion is negligible. At 5 C (a typical temperature at high latitudes), a rise of 1 C...

Atmospheric temperature observed by satellites

Since 1979 meteorological satellites flown by the National Oceanic and Atmospheric Administration NOAA of the United States have carried a microwave instrument, the Microwave Sounding Unit MSU , for the remote observation of the average temperature of the lower part of the atmosphere up to about 7 km in altitude. Figure 4.3b shows the record of global average temperature deduced from the MSU and compares it with data from sounding instruments carried on balloons for the same region of the...

The greenhouse effect

Natural Greenhouse Gases

This view of the rising Earth greeted the Apollo 8 astronauts as they came out from behind the Moon. This view of the rising Earth greeted the Apollo 8 astronauts as they came out from behind the Moon. THE BASIC principle of global warming can be understood by considering the radiation energy from the Sun that warms the Earth's surface and the thermal radiation from the Earth and the atmosphere that is radiated out to space. On average these two radiation streams must balance. If the balance is...

Energy intensity and carbon intensity

Carbon And Energy Intensity Japan

An index that provides an indication of a country's energy efficiency is the ratio of annual energy consumption to gross domestic product GDP known as the energy intensity. Figure 11.3 shows that from 1970 to 2005 world total GDP increased by a factor of about 3 while energy consumption increased by a factor of about 2, the result being a decrease in energy intensity of about 30 or an average of about 1 per year. There are substantial differences between countries. Within the OECD, Denmark,...

Energy policy in the UK

A number of important reports concerned with energy policy have been published in the UK since the year 2000. The first of these is Energy in a Changing Climate published in 2000 by the Royal Commission on Environmental Pollution (RCEP)74 - an expert body that provides advice to government. It supported the concept of 'contraction and convergence' (Figure 10.5) as a basis for future international action to reduce greenhouse gas emissions and pointed out that application of this concept would...

Comparison with observations

Global Warming Comparison

More than 20 centres in the world located in more than ten countries are currently running climate models of the kind I have described in which the circulations of the atmosphere and the ocean are fully coupled together. Some of these models have been employed to simulate the climate of the last 150 years allowing for variations in aspects of natural forcing (e.g. solar variations and volcanoes) and anthropogenic forcings (i.e. increases in the concentrations of greenhouse gases and aerosols)....

Other greenhouse gases Methane

How Does Methane Create Global Warming

Methane is the main component of natural gas. Its common name used to be marsh gas because it can be seen bubbling up from marshy areas where organic material is decomposing. Data from ice cores show that for at least 2000 years before 1800 its concentration in the atmosphere was about 700 ppb. Since then its concentration has more than doubled (Figure 3.6a) to a value that the ice core record shows is unprecedented over at least the last 650 000 years. During the 1980s it was increasing at...

The future of climate modelling

Very little has been said in this chapter about the biosphere. Chapter 3 referred to comparatively simple models of the carbon cycle which include chemical and biological processes and simple non-interactive descriptions of atmospheric processes and ocean transport. The large three-dimensional global circulation climate models described in this chapter contain a lot of dynamics and physics but no interactive chemistry or biology. As the power of computers has increased, it has become possible...

Realising the Climate Convention Objective

Having recommended a choice of stabilisation level, a large question remains how can the nations of the world work together to realise it in practice It is instructive first to look at annual emissions of greenhouse gases expressed as CO2e and per capita. Averaged over the world in 2004 they were about 6.5 t CO2e ( 1.8 t C) per capita but they varied very much from country to country (Figure 10.4). For developed countries, including transitional economy countries, in 2000 they averaged 16 t...

Solar energy in building design

Solar Stirling Engine Electricity

Flap to control reverse flow at night All buildings benefit from unplanned gains of solar energy through windows and, to a lesser extent, through the warming of walls and roofs. This is called 'passive solar gain' for a typical house in the UK it will contribute about 15 of the annual space heating requirements. With 'passive solar design' this can relatively easily and inexpensively be increased to around 30 while increasing the overall degree of comfort and amenity. The main features of such...

Projections of global average temperature

When information of the kind illustrated in Figures 6.1 and 6.2 is incorporated into simple or more complex models, projections of climate change can be made. As we have seen in earlier chapters, a useful proxy for climate change that has been widely used is the change in global average temperature. The projected increases in global average near surface temperature over the twenty-first century due to increase in greenhouse gases and aerosols as assumed by the six marker SRES scenarios is...

Impacts on Africa

Africa is one of the most vulnerable continents to climate change and variability, a situation that is exacerbated by existing developmental challenges such as endemic poverty complex governance and institutional dimensions limited access to capital, including markets, infrastructure and technology ecosystem degradation and complex disasters and conflicts - all of which contribute to Africa's weak adaptive capacity to climate change.61 Some projected climate impacts for Africa are summarised as...

Socolow and Pacalas Wedges

A simple presentation of the type of changes that will be required has been created by Professors Socolow and Pacala of Princeton University.8 To counter the likely growth of global carbon dioxide emissions from 2005 to 2055, seven 'wedges' of reduction are proposed Figure 11.5 , each wedge amounting to 1 giga-tonne of carbon per year 3.66 gigatonnes of carbon dioxide per year in 2055 or 25 gigatonnes in the period 2005-55. Many combinations of technologies can be proposed to fill the wedges....

Weather forecasting and chaos

The science of chaos has developed rapidly since the 1960s (when a meteorologist, Edward Lorenz, was one of its pioneers) along with the power of electronic computers. In this context, chaos4 is a term with a particular technical meaning (see Glossary). A chaotic system is one whose behaviour is so highly sensitive to the initial conditions from which it started that precise future prediction is not possible. Even quite simple systems can exhibit chaos under some conditions. For instance, the...

Efficiency of appliances

There is large potential for reducing the electricity consumption from appliances used in domestic or commercial buildings. If, in replacing appliances, everyone bought the most efficient available, their total electricity consumption could easily drop by more than half. Take lighting for instance. One-fifth of all electricity used in the United States goes directly into lighting. This can easily be reduced by the wider use of compact fluorescent light bulbs which are as bright as ordinary...

Global warming and climate change

Hurricane Wilma hit Florida's southern west coast on 24 October 2005. THE PHRASE 'global warming' has become familiar to many people as one of the most important issues of our day. Many opinions have been expressed concerning it, from the doom-laden to the dismissive. This book aims to state the current scientific position on global warming clearly, so that we can make informed decisions on the facts. In the year 2060 my grandchildren will be approaching 70 years old what will their world be...

Changes in climate extremes

The last section looked at the likely regional patterns of climate change. Can anything be said about likely changes in the frequency or intensity of climate extremes in the future It is, after all, not the changes in average climate that are generally noticeable, but the extremes of climate - droughts, floods, storms and More More cold record weather cold weather extremes of temperature in very cold or very Increase in mean warm periods - which provide the largest impact on our lives (see...

IEA World Energy Outlook

In chapters 10 and 11, I have already referred extensively to the work of the International Energy Agency (IEA) and to their Energy Technology Perspectives published in June 2008 that outlines an energy future up to 2050 that aims at stabilization of atmospheric carbon dioxide consistent with a rise in global surface temperature of less than 2 C. The IEA's annual World Energy Outlook (WEO) is the most important world publication in the energy field. The WEO published in November 2008 includes...

A zero carbon future

In Chapter 10 beginning on page 293, after an analysis of the increasing seriousness of the consequences of global warming as the temperature rises, arguments were put forward for setting a target for the increase of global average temperature of no greater than 2 deg C above its pre-industrial level. Inspection of the profile of CO2 emissions in the IEA BLUE Map scenario published in Energy Technology Perspectives 2008 (Figures 11.4 and 10.3), which aims to meet this target, shows that the...

Palaeoclimate reconstruction from isotope data

The isotope 18O is present in natural oxygen at a concentration of about 1 part in 500 compared with the more abundant isotope 16O. When water evaporates, water containing the lighter isotope is more easily vaporised, so that water vapour in the atmosphere contains less 18O compared with sea water. Similar separation occurs in the process of condensation when ice crystals form in clouds. The amount of separation between the two oxygen isotopes in these processes depends on the temperatures at...

Adaptation to climate change

As we have seen, some of the impacts of climate change are already apparent. A degree of adaptation63 therefore has already become a necessity. Numerous possible adaptation options for responding to climate change have already been identified - examples are given in Table 7.2. Because it takes some decades for the oceans to warm, there also exists a substantial commitment to further climate change even if carbon dioxide emissions were to be halted. Urgent action is therefore necessary to...

Changes in the ocean thermohaline circulation

Climate Change And Thc

The ocean thermohaline circulation THC was introduced in the box on page 120 in Chapter 5, where Figure 5.18 illustrates the deep ocean currents that transport heat and fresh water between all the world's oceans. Also mentioned in the box was the influence on the THC in past epochs of the input of large amounts of fresh water from ice melt to the region in the North Atlantic between Greenland and Scandinavia where the main source region for the THC is located. With climate change due to...

The Kyoto Protocol

At the first meeting after its entry into force held in Berlin in 1995, the Parties to the Climate Convention (i.e. all the countries that had ratified it) decided that they needed to negotiate a more specific and quantified agreement than the Convention on its own provided. Because of the principle in the Convention that industrialised countries should take the lead, a Protocol was formulated that required commitments from these countries (known as Annex I countries) for specific quantitative...

Heatwaves in Europe and India

Record extreme temperatures were experienced in Europe during June, July and August 2003. At many locations temperature rose to over 40 C. In France, Italy, the Netherlands, Portugal and Spain, over 20, 000 (possibly as many as 35 000) additional deaths were attributed to the unrelenting heat. Spain, Portugal, France and countries in Central and Eastern Europe suffered from intense forest fi res.59 Figure 7.19 illustrates the rarity of this event showing that it is well outside normal climate...

Notes For Chapter

Notes Global Warming

1 For comprehensive detail about climate change impacts, see Parry et al. eds. Climate Change 2007 Impacts. 2 From Summary for policymakers in, McCarthy, J. J., Canziani, O., Leavy, N. A., Dotten, D. J., White, K. S. eds. 2001. Climate Change 2001 Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge Cambridge University Press see also Parry et al. eds. Climate Change 2007 Impacts. 3...

Stabilisation of carbon dioxide concentrations

Carbon dioxide, as we have seen, is the most important of the greenhouse gases that is increasing through human activities. As we saw in Chapter 3, emissions of carbon dioxide into the atmosphere from anthropogenic sources result from fossil fuel burning (about 80 ) and from land-use changes (about 20 ) - mainly deforestation. Reduction in emissions from land-use changes was considered earlier in the chapter. Reductions in emissions from fossil fuel burning will be the subject of the next...

Stabilisation of emissions

The target for short-term action proposed for developed countries by the Climate Convention was that, by the year 2000, greenhouse gas emissions should be brought back to no more than their 1990 levels. In the run-up to the Rio conference, before the Climate Convention was formulated, many developed countries had already announced their intention to meet such a target at least for carbon dioxide. They would do this mainly through energy-saving measures, through switching to fuels such as...

Reduction in sources of greenhouse gases other than carbon dioxide

Methane, nitrous oxide and the halocarbons are greenhouse gases, less important than carbon dioxide, all of which show increases at the present time. In Figures 6.1 and 6.2 and Table 6.1 are shown the emissions, atmospheric concentrations and radiative forcing of these gases estimated for the twenty-first century under the various SRES scenarios, assuming no special action to reduce them. Is it possible that these further increases can be slowed or eliminated We consider them in turn. Methane...

World energy demand and supply

Electric Circuits Model House

Most of the energy we use can be traced back to the Sun. In the case of fossil fuels (coal, oil and gas) it has been stored away over millions of years in the past. If wood (or other biomass including animal and vegetable oils), hydropower, wind or solar energy itself is used, the energy has either been converted from sunlight almost immediately or has been stored for at most a few years. These latter sources of energy are renewable they will be considered in more detail later in the chapter....

Carbonfree electricity supply

Bedrock Strata

We have already noted that moving as rapidly as possible to carbon-free electricity is key to achieving the level of overall reductions of carbon dioxide emissions required by 2030 and 2050. Contributions to this movement can come in five ways (1) increases in efficiency, (2) decreases in carbon intensity, (3) by widespread deployment of carbon capture and storage, (4) by the use of nuclear energy, (5) through the use of all possible renewable energies. From the long-term point of view, (1) and...

Policy instruments

Action in the energy sector on the scale required to mitigate the effects of climate change through reduction in the emissions of greenhouse gases will require significant policy initiatives by governments in cooperation with industry. Some of these initiatives are the following 61 putting in place appropriate institutional and structural frameworks energy pricing strategies (carbon or energy taxes and reduced energy subsidies) reducing or removing other subsidies (e.g. agricultural and...

Fuel cell technology

A fuel cell converts the chemical energy of a fuel directly into electricity without first burning it to produce heat.64 It is similar to a battery in its construction. Two electrodes (Figure 11.24) are separated by an electrolyte which transmits ions but not electrons. Fuel cells possess high theoretical efficiency. Typical efficiencies in practice are in the range of 40-80 . Hydrogen for fuel cells may be supplied from a wide variety of sources, from coal65 or other biomass (see Note 31),...

The Precautionary Principle

Some of these arguments for action are applications of what is often called the Precautionary Principle, one of the basic principles that was included in the Rio Declaration at the Earth Summit in June 1992 (see box below). A similar statement is contained in Article 3 of the Framework Convention on Climate Change (see box on pages 291-2 in Chapter 10). We often apply the Precautionary Principle in our day-to-day living. We take out insurance policies to cover the possibility of accidents or...

Questions

1 There is a debate regarding the relationship of humans to the environment. Should humans be at the centre of the environment with everything else and other life related to the human centre - in other words an anthropocen-tric view Or should higher prominence be given to the non-human part of nature in our scheme of things and in our consideration of values - a more ecocentric view If so, what form should this higher prominence take 2 How far can science be involved in the generation and...

Biomass projects in rural areas in the developing world

In much of the developing world, most of the population live in areas where there is little or no access to electricity or modern energy services. There is large potential for creating local biomass projects to provide such services. Figure 11.13 shows a schematic of a modern biogas plant and examples are given of pilot projects,42 all of which could be replicated many times. India, still a predominantly agriculture-based country, produces approximately 400 million tonnes of agro waste every...

Local energy provision in Bangladesh

In a box earlier in the chapter on page 337, I outlined the components of a strategy for energy provision, one of which emphasised the value of local and distributed sources of energy as opposed to centralised sources in large units serving large grid networks. An example of local provision is Grameen Shakti (meaning Rural Power) in Bangladesh - a subsidiary of Professor Yunus's famed Grameen Bank - that has developed an affordable solar home system (Figure 11.19) offered to rural communities...

Feedbacks in the biosphere

As the greenhouse gases carbon dioxide and methane are added to the atmosphere because of human activities, biological or other feedback processes occurring in the biosphere (such as those arising from the climate change that has been induced) influence the rate of increase of the atmospheric concentration of these gases. These processes will tend either to add to the anthropogenic increase (positive feedbacks) or to subtract from it (negative feedbacks). Two feedbacks, one positive (the...

The carbon dioxide fertilisation effect

An important positive effect of increased carbon dioxide concentrations in the atmosphere is the boost to growth in plants given by the additional carbon dioxide. Higher carbon dioxide concentrations stimulate photosynthesis, enabling plants to fix carbon at a higher rate. This is why in glasshouses additional carbon dioxide may be introduced artificially to increase productivity. The effect is particularly applicable to what are called C3 plants (such as wheat, rice and soya bean), but less so...

Sustainability also a global challenge

To bring in the broader context demanded by global solutions, in Chapters 8 and 9 the concept of sustainable development was introduced. Sustainability is a modern term that is widely used that takes into account our breadth of concern about the environment and the Earth's resources.1 Just what do we mean by sustainability Imagine you are a member of the crew of a large spaceship on a voyage to visit a distant planet. Your journey there and back will take many years. An adequate, high-quality,...

Future emissions of carbon dioxide

To obtain information about future climate we need to estimate the future atmospheric concentrations of carbon dioxide, which depend on future anthropogenic emissions. In these estimates, the long time constants associated with the response of atmospheric carbon dioxide to change have important implications. Suppose, for instance, that all emissions into the atmosphere from human activities were suddenly halted. No sudden change would occur in the atmospheric concentration, which would decline...

Stewards of the Earth

Washington Laghi Alpini Natura

The relationship between humans and the Earth that I have been advocating is often described as one of stewardship. We are on the Earth as its stewards. The word implies that we are carrying out our duty as stewards on behalf of someone else - but whom Some environmentalists see no need to answer the question specifically, others might say we are stewards on behalf of future generations or on behalf of a generalised humanity. A religious person would want to be more specific and say that we are...

Energy and carbon dioxide savings in transport

Transport is responsible for nearly one-quarter of greenhouse gas emissions worldwide. It is also the sector where emissions are growing most rapidly Figure 11.9 . Road transport accounts for the largest proportion of this, over 70 , shipping around 20 and air transport about 10 .23 The world population Figure 11.9 Historical and projected carbon dioxide emissions from transport by modes, 1970-2050. Projected data by the World Business Council on Sustainable Development WBCSD under a...

Other renewable energies

We have so far covered the renewable energy sources for which there is potential for growth on a scale that can make a substantial contribution to overall world energy demand. We should also mention briefly other renewable energy technologies that contribute to global energy production and which are of particular importance in certain regions, namely geothermal energy from deep in the ground and energies from the tides, currents or waves in the ocean. The presence of geothermal energy from deep...

Impacts in coastal areas

Bangladesh Sea Level Rise

A rise in average sea level of 10 to 20 cm by 2030 and about up to 1 metre by the end of the next century may not seem a great deal. Many people live sufficiently above the level of high water not to be directly affected. However, half of humanity inhabits the coastal zones around the world.11 Within these, the lowest lying are some of the most fertile and densely populated. To people living in these areas, even half a metre increase in sea level can add enormously to their problems. Their...

The insurance industry and climate change

The impact of climate on the insurance industry is mainly through extreme weather events. In developing countries there may be very high mortality from extreme weather but relatively small costs to the industry because of low insurance penetration. In developed countries the loss of life may be much less but the costs to the insurance industry can be very large. Figure 1.2 illustrates the large growth in weather-related disasters and the associated economic and insured losses since the 1950s...

Model projections

Results that come from the most sophisticated coupled atmosphere-ocean models of the kind described in the last chapter provide fundamental information on which to base climate projections. However, because they are so Table 6.1 Radiative forcing (W m-2) globally averaged, for greenhouse gases and aerosols from the year 1750 to 2005 and from SRES scenarios to 2050 and 2100 a Including both direct and indirect effects. demanding on computer time only a limited number of results from such models...

Some global economics

So far our attempt to balance uncertainty against the need for action has been considered in terms of issues. Is it possible to carry out the weighing in terms of cost In a world that tends to be dominated by economic arguments, quantification of the costs of action against the likely costs of the consequences of inaction must at least be attempted. It is also helpful to put these costs in context by comparing them with other items of global expenditure. The costs of anthropogenic climate...

Biomass energy

Second in current importance as a renewable energy source is the use of bio-mass.37 The annual global primary production of biomass of all kinds expressed in energy units is about 4500 EJ ( 107 Gtoe). About 1 of this is currently turned into energy mostly in developing countries - we have labelled it 'traditional biomass'. It has been estimated that about 6 of the total could become available from energy crops taking into account the economics of production and the availability of suitable...

The past million years

To go back before recorded human history, scientists have to rely on indirect methods to unravel much of the story of the past climate. A particularly valuable information source is the record stored in the ice that caps Greenland and the Antarctic continent. These ice caps are several thousands of metres thick. Snow deposited on their surface gradually becomes compacted as further snow falls, becoming solid ice. The ice moves steadily downwards, eventually flowing outwards at the bottom of the...

Where are we heading Components of energy strategy

(1) Planning for the long term must be a priority. Long timescales up to 50 or 100 years are involved in many factors that make up the climate change issue, for instance, the lifetime of carbon dioxide in the atmosphere, the lag due to the ocean in the realisation of climate change or the typical life of energy infrastructure. (2) Not all potential technologies are at the same stage of development. Promising technologies need to be brought to the starting gate so that they can properly compete....

The Kyoto mechanisms

The Kyoto Protocol includes three special mechanisms to assist in emissions reductions. Joint implementation (JI) allows industrialised countries to implement projects that reduce emissions or increase removals by sinks in the territories of other industrialised countries. Emissions reduction units generated by such projects can then be used by investing Annex I countries to help meet their emissions targets. Examples of JI projects could be the replacement of a coal-fired power plant with a...

Energy and carbon dioxide savings in industry

Industry currently accounts for nearly one-third of worldwide primary energy use and about one-quarter of carbon dioxide emissions of which 30 comes from the iron and steel industry, 27 from non-metallic minerals (mainly cement) and 16 from chemicals and petrochemicals production.27 Substantial opportunities exist for efficiency savings in all these areas. The application of appropriate control technologies, other best-available technologies (BAT) and more widespread combined heat and power...

The worlds forests and deforestation

The total area covered by forest is almost one-third of the world's land area, of which 95 is natural forest and 5 planted forest.9 About 47 of forests worldwide are tropical, 9 sub-tropical, 11 temperate and 33 boreal. At the global level, the net loss in forest area during the 1990s was an estimated 940 000 km2 (2.4 of total forest area). This was the combined effect of a deforestation rate of about 150 000 km2 per year and a rate of forest increase of about 50 000 km2 per year. Deforestation...

Solar water heating

The essential components of a solar water heater (Figure 11.15) are a set of tubes in which the water flows embedded in a black plate insulated from behind and covered with a glass plate on the side facing the Sun. A storage tank for the hot water is also required. A more efficient (though more expensive) design is to surround the black tubes with a vacuum to provide more complete insulation. Over 10 million households worldwide have solar hot water systems.49 Figure 11.15 Design of a solar...

Global warming global pollution

A hundred years ago, the French painter Claude Monet spent time in London and painted wonderful pictures of the light coming through the smog. London was blighted by intense local pollution - from domestic and industrial chimneys around London itself. Thanks to the Clean Air Acts beginning in the 1950s, those awful smogs belong to the past - although London's atmosphere could be still cleaner. Today, however, it is not just local pollution that is a problem but global pollution. Small amounts...

Some extracts from the United Nations Framework Convention on Climate Change signed by over countries in Rio de Janeiro

Firstly, some of the paragraphs in its preamble, where the parties to the Convention CONCERNED that human activities have been substantially increasing the atmospheric concentration of greenhouse gases, that these increases enhance the natural greenhouse effect, and that this will result on average in an additional warming of the Earth's surface and atmosphere and may adversely affect natural ecosystems and humankind. NOTING that the largest share of historical and current global emissions of...

Technologies for reducing carbon dioxide emissions from motor vehicles

An important recent development is that of the hybrid electric motor car that combines an internal combustion engine with an electric drive train and battery.25 The gains in effi ciency and therefore fuel economy achieved by hybrid vehicles are typically around 50 . They mainly arise from 1 use of regenerative braking with the motor used as a generator and captured electricity stored in the battery , 2 running on the battery and electric traction only when in slow-moving or congested traffic, 3...

Why not wait and see

The debate about climate change not only addresses how much action is required but also when it needs to be taken. In the light of scientific uncertainty, it has often been argued that the case is not strong enough for much action to be taken now. What we should do is to obtain as quickly as possible, through appropriate research programmes, much more precise information about future climate change and its impact. We would then, so the argument goes, be in a much better position to decide on...

Emission scenarios

A principal reason for the development of climate models is to learn about the detail of the likely climate change this century and beyond. Because model simulations into the future depend on assumptions regarding future anthropogenic emissions of greenhouse gases, which in turn depend on assumptions about many factors involving human behaviour, it has been thought inappropriate and possibly misleading to call the simulations of future climate so far ahead 'predictions'. They are therefore...

Buildings energy conservation and efficiency

If we turn lights off in our homes when we do not need them, if we turn down the thermostat by a degree or two so that we are less warm or less cool or if we add more insulation to our home, we are conserving or indeed saving energy. Figure 11.6 Where are we heading - the need for an energy strategy. The boat flies national and UN flags to illustrate the need for national and international strategies. Figure 11.6 Where are we heading - the need for an energy strategy. The boat flies national...

Thermodynamic efficiencies

When considering the efficiency of energy use, it can be important to distinguish between efficiency as defined by the First Law of Thermodynamics and efficiency as defined by the Second Law. The second particularly applies when energy is used for heating. A furnace used to heat a building may deliver say 80 of the energy released by full combustion of the fuel, the rest being lost through the pipes, flue, etc. That 80 is a First Law efficiency. An ideal thermodynamic device delivering 100...

Insulation of buildings

About 1500 million people live in cold climates where some heating in buildings is required. In most countries the energy demand of space heating in buildings is far greater than it need be if the buildings were better insulated (Figure 11.7). Table 11.1 provides as an example details of two houses, showing that the provision of insulation in the roof, the walls and the windows can easily lead to the energy requirement for space heating being more than halved (from 5.8 kW to 2.65 kW). The cost...

Projections for energy investment

The International Energy Agency has also estimated the future financial investment in global energy that will be necessary between 2005 and 2050 under their Reference or Baseline Scenario and the additional investment required to achieve the ACT and the BLUE Map energy scenarios.7 The total cumulative energy investment needs for the Reference scenario over this period is estimated to be about US250 trillion (million million) or about 6 of cumulative world GDP over the period. By far the largest...

Power from nuclear fusion

When at extremely high temperatures the nuclei of hydrogen (or one of its isotopes, deuterium or tritium) are fused to form helium, a large amount of energy is released. This is the energy source that powers the Sun. To make it work on Earth, deuterium and tritium are used from 1 kg, 1 GW can be generated for one day. The supply of material is essentially limitless and no unacceptable pollution is produced. A temperature of 100 million degrees Celsius is required for the reaction to occur. To...

Technology for the longer term

This chapter has concentrated mostly on what can be achieved with available and proven technology during the next few decades. It is also interesting to speculate about the more distant future and what relatively new technologies may become dominant during the twenty-first century. In doing so, of course, we are almost certainly going to paint a more conservative picture than will actually occur. Imagine how well we would have done if asked in 1900 to speculate about technology change by 2000...

Environmental values

What do we value in the environment and how do we decide what we need to preserve, to foster or improve At the basis of our discussion so far have been several assumptions regarding the value or importance of different fundamental attitudes or actions, some of which I have associated with ideas that come from the underlying environmental science. Is it legitimate, however, to make connections of this kind between science and values It is often argued that science itself is value free. But...

Regional climate models

Most of the likely changes that we have presented have been on the scale of continents. Can more specific information be provided about change for smaller regions In Chapter 5 we referred to the limitation of global circulation models (GCMs) in the simulation of changes on the regional scale arising from the coarse size of their horizontal grid - typically 300 km or more.30 Also in Chapter 5 we introduced the regional climate model (RCM) which typically possesses a resolution of 50 km and can...

Wind energy

Two hundred years ago windmills were a common feature of the European landscape for example, in 1800 there were over 10 000 working windmills in Britain. During the past few years they have again become familiar on the skyline especially in countries in Western Europe (for instance, Denmark, Germany, UK and Spain) and in western North America. Slim, tall, sleek objects silhouetted against the sky, they do not have the rustic elegance of the old windmills, but...

Modelling the impact of climate change on world food supply

An example illustrating the key elements of a detailed study of the impact of climate change on world food supply is shown in Figure 7.12.45 A climate change scenario is fi rst set up with a climate model of the kind described in Chapter 5. Models of different crops that include the effects of temperature, precipitation and carbon dioxide are applied to 124 different locations in 18 countries to produce projected crop yields that can be compared with projected yields in the absence of climate...

Wind power on Fair Isle

A good example of a site where wind power has been put to good effect is Fair Isle, an isolated island in the North Sea north of the Scottish mainland.48 Until recently, the population of 70 people depended on coal and oil for heat, petrol for vehicles and diesel for electricity generation. A 50-kW wind generator was installed in 1982 to generate electricity from the persistent strong winds of average speed over 8 m s-1 (29 km h-1 or 18 mph). The electricity is available for a wide variety of...

Poverty and population growth

The Prince of Wales, in addressing the World Commission on Environment and Development on 22 April 1992, spoke as follows 7 I do not want to add to the controversy over cause and effect with respect to the Third World's problems. Suffice it to say that I don't, in all logic, see how any society can improve its lot when population growth regularly exceeds economic growth. The factors which will reduce population growth are, by now, easily identified a standard of health care that makes family...

Longerterm climate change

Most of the projections of future climate that have been published cover the twenty-first century. For instance, the curves plotted in Figures 6.1 to 6.6 extend to the year 2100. They illustrate what is likely to occur if fossil fuels continue to provide most of the world's energy needs during that period. From the beginning of the industrial revolution until 2000 the burning of fossil fuels released approximately 300 Gt of carbon in the form of carbon dioxide into the atmosphere. Under the...