HL Deb 30 November 1978 vol 396 cc1442-70

5.15 p.m.

Lord TANLAW rose to ask Her Majesty's Government whether there is cause for concern in the current increase in atmospheric carbon dioxide and apparent change in global weather patterns. The noble Lord said: My Lords, I should first like to put on record my apologies for any inconvenience to the House in having to adjourn, I myself being the cause of the adjournment. The main object of asking this rather technical Question is to discover the attitude of Her Majesty's Government towards the whole problem of atmospheric carbon dioxide and the subsequent social and economic impact of a sudden and unpredictable change in the world's weather patterns.

This problem is an entirely novel one in that it may create an entirely new set of conditions to be met by Government agencies at national and international level. Therefore, I shall make an attempt to describe first, in the briefest possible terms, what is popularly known as the "greenhouse effect", how I believe excessive atmospheric carbon dioxide may affect the world climate.

Until this present time in history the amount of carbon dioxide created by nature and by man has been cleaned naturally by the oceans and counteracted by oxygen produced from the large forest areas and vegetation on our planet's surface. It has been until now a delicate balance, and the concern today is that man's industrial development, combined with greatly increased use of fossil fuels, may have created for the first time an imbalance in this atmospheric change-over. The surplus carbon dioxide created by human activity may now be adding extra heat to the lower atmosphere or troposphere, which is simultaneously cooling the stratosphere or upper atmosphere. The general climatic effect of this process simply means that the lower levels of the atmosphere will hold more water vapour while the absorption of radiation by that water vapour enhances the warming effect on the global surface.

It has been estimated that if the amount of atmospheric carbon dioxide were to double between now and the year 2000 this might produce an average global warming of between 5 and 10 degrees Centigrade in the polar regions, and this in turn could lead to substantial melting of the ice cap and widespread flooding; whereas a more modest, and more likely, increase of between only 2 and 3 degrees Centigrade—as has been suggested by Dr. Mason, the head of our Meteorological Office in a recent article in the magazine Nature—might well lead to increased food production by prolonging the growing season, and, furthermore, produce considerable savings in energy consumption. In the second scenario there could be some unforeseen and offsetting disadvantages, but these should be assessed before assuming a catastrophe situation.

For some years now scientists concerned with meteorology and climatology have been expressing at times conflicting conclusions, but unanimous concern at the outcome of the processes I have described. Consequently, the World Meteorological Organisation, the International Council of Scientific Unions, in collaboration with other international agencies, are planning a world climate programme spanning the two decades from 1980 to 2000. This will be preceded by the World Climate Conference in Geneva next year. This programme will have three main elements, which are climate data and applications, an investigation of the impacts of climate on human activities, and, finally, research of climatic change and variability. What all this means to me as a non-scientist is that something is going on in the atmosphere which may not be fully understood, but its effects could change the existing pattern of life for society throughout the world. Therefore, it is surely time to ask whether Her Majesty's Government are participating in these international investigative programmes, and whether everything possible is being planned to ensure that, if any disruptions do occur in this country, they will be minimised or anticipated by previously prepared Government plans.

This leads me on to ask for confirmation from the noble Lord the Minister that, whatever plans the Government may have in mind, they have co-ordinated and directed them by scientists who are both meteorologists and climatologists, and not by various Civil Service departments. I say that bearing in mind that these subjects are relatively new and, because of their nature, have to draw upon a whole range of differing skills and technologies. The very varied nature of the disciplines involved makes this subject, to my mind, totally unsuitable for management by a single Government Department or Departments.

I hope that the Minister will be able to advise me that a committee will be established with full powers to draw on the expertise that exists within Government departments, as well as the scientific community as a whole, and that that committee will have direct access to the Cabinet. It is also to be hoped that the Minister will give an undertaking that, if such a committee is put into being, its findings and conclusions will be made available to the public. I ask that because up until now, in all the energy equations that I have seen and the results of the energy conferences which I have attended, the global weather pattern has not been part of the published papers.

The other reason why I have asked Her Majesty's Government to take note of these matters at this time is that decisions will have to be made within the next three years or so as to the sources of energy that will be used at the turn of the century. If it is proved that the burning of fossil fuels will change the world weather pattern, then complete reconsideration must be given to current thinking on not only the sources of energy we intend to use in this country but those throughout the industrial world as it exists and in those countries which are about to become industrial.

The scenarios that I have described were based on the assumption that there will be a doubling up of the carbon dioxide in the atmosphere within the next 30 years. To my mind that is no longer a probability, but a certainty when one considers that the majority of people in the developing world have not begun to use the quota of energy consumed today by the industrial nations. If one combines that with the savage programmes of deforestation that have occurred in South America, India and Asia, there would appear to be no difficulty in doubling the amount of carbon dioxide in the atmosphere, whether we like it or not.

On the other hand, I cannot see how we can deny the developing world from following the same course of technical development, and achieving the same levels of comfort that we ourselves have reached. Indeed, we are hell-bent on providing future industrial nations like, for example, China with all the latest and most energy-consuming engines of our technology. Therefore, it is a matter of the greatest urgency that we know as soon as possible the effects of these inevitable developments in order that, if they prove to be detrimental to the weather system, their impact on society may be minimised as far as possible.

The energy equations to date have been based, in my view quite correctly, on extrapolations of the weather patterns for the past 30 years. It has been assumed, because there is no other basis, that the next 30 years will produce the same variety of weather. If the information from the World Weather Watch and the World Climate Programmes indicates an entirely different or irregular weather pattern, that in turn must mean that the future energy calculations will be wrong yet again. Therefore, if the weather element is incorporated into all future energy equations, the results may be different in that a much more flexible approach to anticipating future energy requirements will have to be made and there may be a slightly better chance in my view of obtaining more accurate results.

Some people may say that the predictions I have suggested are at best theoretical, and at worst unlikely to happen in the foreseeable future or even within the next 100 years. I was one of those people not so long ago, until I became completely convinced that the time spans that are being suggested by the climatologists and the meteorologists are very short indeed. What is more, they indicate that whatever process may be at work in the atmosphere it is a rapid one.

I now come to the second half of my Question, which is to inquire if the recent exceptional weather conditions that have been reported from all parts of the globe in the last few years are a first indication that man's industrial activities have already begun to affect the global weather pattern. I have read of no proper explanation for the extraordinary North American winter of 1977–78 or for the British drought in 1975–76. We are already aware of the tragic flooding in Northern India, and there are reports of heavy and exceptional rainfall occurring on the African Continent outside the normal rainy season. It is too early to say this evening, but I would be very surprised if this November does not prove to be the warmest recorded in Southern England for at least 200, if not 300, years.

Unfortunately, at this stage scientific proof that these anomalies are directly linked to increased atmospheric carbon dioxide may not be possible, in spite of the most sophisticated computers in the world that are operated by the Meteorological Office at Bracknell. However, it may be worth mentioning that Britain, along with the United States, is at present the world leader in meteorological science, and it is to be hoped that the Government will support the studies being undertaken under the very competent direction of Dr. Mason, to whom I referred earlier. Nevertheless, it will be unlikely that the results of the various world climate programmes will be available for at least 10 years. My concern today is whether, if the climate does change more rapidly than any predictions that have been made so far, the Government are prepared to cope with the impacts this may have on—to give two examples—agriculture and shore-based power stations.

If I may return for a moment to the British drought, the Government's reactions to that were, to my mind, not particularly encouraging. It would appear that the Government were fully aware of the impending drought many months before it occurred but took no action either nationally or through directions to local government authorities. Instead, the Government waited until there was a meteorological indication that the stationary warm front was on the move again, and only then decided to create a Minister for Drought. Although no real harm was done, I should like the Minister to give some assurance that any future situation will be taken a little more seriously and dealt with perhaps more swiftly than was the case in 1976.

In conclusion, my Question raises the far wider issues of communication between the scientific community, Government agencies and the general public. Scientists work within an entirely different framework from that of us in Parliament. Their statements have to be more restrained and are based on proven scientific fact, and often because of that their conclusions are not necessarily unanimous. That is particularly the case with questions of weather and climate. Therefore, we cannot hope to expect any definite answers to the very wide-ranging questions raised in the debate. However, what we can, and I believe should, expect from the Government is an assurance that the lines of communication with all the scientists concerned are kept fully open on this subject.

My own view, for what it is worth, and it is no more than a guess, is that the seasons have already begun to change. That change will progress with a general surface warming, and the net effects may be both beneficial and agreeable rather than catastrophic—provided the "greenhouse effect", to which I have referred, does not turn into a runaway situation. The FAO has just announced that world food production has increased by 3 to 3.5 per cent. Therefore the recent weather changes appear, so far, to augur well for mankind. On that note I should like to conclude, and it is an optimistic note at that.

5.28 p.m.

Lord O'HAGAN

My Lords, after listening to the noble Lord I am sure that your Lordships are grateful that Lord Tanlaw finally arrived. At first I thought that perhaps he had become unhorsed by the changing pattern of weather conditions, or was even suffering from an overdose of carbon dioxide. However, both of those gloomy prognostications were untrue. Like him, when I first began to study this question I thought it was the type of subject which deserved more attention from Dr. Who than from your Lordships' House with serious political or scientific examination. However, something strange is going on in the part of the world in which I live. Barley is in "ear" at this time of the year and, although it is a pleasure to me that it is the "greenhouse effect" or the warming up of the atmosphere which should be blamed for things that arc changing for the worse, instead of our membership of the EEC, it is nevertheless, as the noble Lord, Lord Tanlaw, has indicated in his remarks, much more than a joke.

It is not only a matter for farmers and the agricultural community and those who are inconvenienced by the changes in the climate. It is something which should, and will, play a very important part in the centre of the discussion about the likely sources of energy in the years to come and those which are safest to use. What we are talking about today must be considered when we are discussing how much nuclear power we should rely on in the future, both for this country and for the industrialised world as a whole.

Therefore I should like to welcome the opportunity that the noble Lord has taken for posing this wide question. I believe that the particular subject that he has chosen to raise illustrates a need for an adaptation of the British Government machine to a changing political and scientific environment. That sounds as bad as the jargon in scientific journals, but I mean that on our own we cannot make a real contribution to doing something about the problems to which the noble Lord, Lord Tanlaw, is addressing himself.

The questions that I should like to ask the Minister—we have a Minister for bad weather as they have a Minister for drought in the other place—are as follows: What has been the response of the British administrative machine so far? Which Ministry is primarily responsible for, and in charge of, co-ordinating the other Ministries? Who is pressing for activity within the European Community? Are the joint research programmes, which are conducted at European level, looking at this subject?

If the weather patterns change and the Polar ice cap melts so that the level of the sea rises, some of our partners in the Community would be among the countries most likely to suffer the worst effects, particularly the Netherlands. Therefore, we could expect our fellow members of the Community to have a direct interest in looking at the possibilities that affect Europe as a whole in the sort of questions raised tonight by the noble Lord, Lord Tanlaw.

It would be a welcome change if this Government were to put forward constructive ideas for activity at a joint level in the Community. We have a high and deserved scientific reputation. If one makes a study of the opinion polls regularly conducted by the Commission, I believe that one will find that joint scientific research is something which all the people in all the member States have regularly said they wish to be increased among the activities of the EEC. It is something which is welcomed rather than something which is resented.

Therefore I would add to the questions of the noble Lord, Lord Tanlaw, about the participation of Her Majesty's Government at an international level in discussions and consultations, a question about our own preparations within our own Departments and what the state of play is there, and a question about activities within the EEC and our contributions there. Somewhere between the two I would ask whether any thought has been given to commissioning the Central Policy Review Staff to look into this subject. It might well be a field in which they could make practical recommendations, having taken into account specialist opinion commissioned for the purpose. If the CPRS were to issue a paper, to which Government credit did not attach and to which the name of the Government was not committed, it might lead to the kind of informed discussion which the noble Lord, Lord Tanlaw, was hoping to promote.

Finally, I wonder whether the noble Baroness, Lady Birk, has any information about the amount of research that is currently being sponsored by different Government Departments through the Research Councils in scientific disciplines which would affect the subject that we are discussing tonight. I think that all the activities which I have described—co-ordination within Whitehall, activities in the international fora and the advancement of co-operation in the European field—could not proceed satisfactorily without there first being an adequate scientific investigation. If we are to continue to hold our deserved scientific reputation in this field, it can come about only through a continued programme of training for those who are skilled in these disciplines, or who want to be skilled in these disciplines, and a continued programme of funding for research projects which can throw up the information for those in other spheres to take political decisions which will lead to activity that may begin to deal with this problem.

I do not know whether or not this question is a serious one, or if it is a question that one can dismiss. However, until we can be certain that it can be dismissed, we should go on investigating. I believe that we have the capability to make a contribution to the solution to this problem. Without encouraging the Government to spend huge sums on this subject as against any other, I hope that we can have a reassuring answer from the noble Baroness tonight that there is at least the administrative capacity to begin to co-ordinate our efforts, so that we are using what skills and what resources we have in the most effective way.

5.37 p.m.

Lord RITCHIE-CALDER

My Lords, I want to thank the noble Lord, Lord Tanlaw, for giving us the opportunity to discuss this question. If the noble Lord, Lord O'Hagan, had any doubts about it, I can tell him categorically and emphatically that this is a very serious question. In fact, it is no longer a question; that is to say, we may have endless debates on the question of the climate because the subject is just as big as the climate itself. But one thing is now perfectly clear: the increase in the carbon-dioxide content of the atmosphere is, as I say, beyond dispute. One can argue about how one quantifies it. One can argue about the detail, but about the general facts one cannot argue.

Weather is always with us, but the Question which has been posed by the noble Lord, Lord Tanlaw, is particularly timely because, as he has pointed out, next year this subject will be commanding—as it should (and I may say, rather belatedly in the total sense)—a great deal of international attention and intense activity. I am getting on in years and am beginning to despair of being listened to, but the fact is that in 1963 the United Nations Conference on Science and Technology spelled this out in the same terms as those in which we are spelling it out now. That was in 1963, 15 years ago. The debate was about the carbon dioxide content of the atmosphere.

As has been pointed out, the World Climate Conference will meet in February, and in addition to the weathermen and the climatologists there will be the biologists, the farming experts, the engineers and the economists, all gathered together in Geneva. They will help to map the tasks of the World Climate Programme. The global weather experiment, to which the noble Lord, Lord Tanlaw, referred, will, in fact, mobilise pretty extensive resources, although whether they will be sufficient, I am not sure. It will mobilise the resources of the entire world to study the weather as it has never been studied before. Some 9,200 land-based stations and weather-ships, deployed at sea, will be reinforced by five weather satellites positioned over the Equator, by balloons and by unmanned buoys strung out throughout the oceans reporting back scientific information to land-based computers. The weather, which is the atmosphere continuously in motion, will be passing through a sieve of stations and all the information will be filtered out and fed to the most powerful computers available in order to simulate the weather and climatic systems.

The matter can only be dealt with globally. I have a great deal of sympathy with Lord O'Hagan's questions, and I support all the questions Lord Tanlaw put, but as we know only too well weather is not a parochial question; it is not a national question; it is not a European Community question; it is a global question, and that is where it is, and should be, dealt with. That is where in the next year we shall be dealing with it. Weather has no frontiers. No Government, however scientifically and technologically endowed—and I agree with Lord Tanlaw that we in this country have one of the best meteorological set-ups in the world—can tackle it.

We do not need a world climate conference to tell us that the weather is changing. We know it in this country. We say it is weird, abnormal. The noble Lord, Lord O'Hagan, tells us that barley is heading up, et cetera. We say it is abnormal, but what was the norm? We remember good summers and bad winters, and our weather memories average them out. But there are climatologists who will tell you that the temperate weather we have enjoyed in the first half of this century has been abnormal—a wobble in a cycle. The noble Lord, Lord Tanlaw, touched on the cyclical aspect, and I am not embarking on the arguments about the little ice age, and so forth. I would explain to your Lordships, if I had the time, why it sounds contradictive but it is not contradictive when we talk about the warming-up of the earth. We may be in the beginnings of a part of a cycle which will produce greater extremes. In fact, we may be moving presently into the kind of thing which was evident in the 19th century when we talk about Dingley Dell and Dickensian winters, which we only put on Christmas cards but which we rarely experience at Christmas.

The fact is that these variations may be going back to the kinds of conditions before 1870, which were very hard. We know that in the 16th and 17th centuries, in Shakespeare's time, there was in fact a little ice age. Conditions were very extreme. We know this from the whole of nature. I do not want to get embarked into what would become a pretty involved argument on the general climatic picture. But I will say categorically, and beyond a peradventure, that the weather has changed and will never be the same again. It has changed since 1945–1950. There is no question about that. We have got all these variations; this weirdness, this strangeness, et cetera, which we ourselves recognise in our ordinary lives.

So we have to know what we have to come to terms with, and what it is going to mean in global terms to the 8,000 million people we shall have to feed in the world by the year 2,000. We can think in our immediate experience of recent years of the Sahel famine, which went on for years; of the droughts in the Soviet Union in 1972; and of another manifestation, the catastrophic collapse of the Peruvian fishing industry, which reverberated in America and in Britain in higher food prices, and so on, because we could not get the fishmeal from the Peruvian fishing industry. That was as a result of a hot current generated in the Pacific which killed off the anchovies. It was the equivalent, if you like, of a drought in agricultural terms.

Now we have the disastrous floods in South-East Asia as a result of the wild vagaries of the monsoon. Of course, as we have been reminded, at one stage quite recently we needed a Minister of Drought. We have to know enough to meet such contingencies. I do not want to elaborate, but I would say that there is a consensus that in fact the jet currents which carry our climate have moved South. The main thrust has moved South. We know that the Gulf Stream has been modified geographically and has again apparently moved South, and that we, who get the advantages of the North Atlantic drift, may be in a part of the effects of that situation.

What does that moving south mean? It means that once again you have a sort of Sahel situation where you move possible rain-bearing winds further south. You can have all the perturbances which have produced the catastrophic variations in the monsoons. If we are to become purely domestic, I think most people would agree that the position in this country is quite clearly that at least—because we are intelligent people—we should be thinking about how we are in fact going to change the nature of our crops to meet the contingency. I should like to elaborate on that at some further discussion.

What the noble Lord, Lord Tanlaw, has raised is not the cyclical changes but the man-made effects of the increase in atmospheric carbon. This is not what we play around with called weather-making. There has been a lot of talk about clima-tological warfare—I think it has been written out of the armoury—and the fact is that we do believe that we could set up a blockade of a country and cut off its weather. We do believe, and it has been demonstrated in pretty local circumstances, that we can produce rain artificially by the seeding of clouds, and so on, but that is not what we are talking about. This is, if you like, inadvertent man-made intervention with the weather. It is the cumulative effect of man's industrial activities. In fact, it is another kind of energy crisis, with the recoil effect of energy. Whatever mankind does to increase energy must, by its nature, increase effects on the weather. It does not matter how you look at it, because you are regenerating a new kind of impulse into the system.

I would remind your Lordships that hundred of millions of year ago carbon from primeval forests was locked away in the coal seams, and carbon from the organic life of the seas was locked away in what are now our oil deposits. That carbon was locked away and kept out of circulation for a very long time. The geological vaults were not burgled to any real extent until the Industrial Revolution. During the past century, industry has vomited out of chimney stacks, and vented out of car exhausts, 360 billion tons of fossil carbon into the atmosphere. According to UN statistics the use of fossil fuel has increased every year since 1860 at a remarkably constant rate of 4.3 per cent. per annum.

If the known production of carbon dioxide is compared with the known atmospheric increase, it turns out that roughly one half of the excess carbon has remained in the atmosphere. Estimates of the ability of the oceans to continue to take up carbon dioxide, if we continue to produce it at the exponential rate, suggest that it will not be able to absorb a fraction of 50 per cent. in the decades ahead.

Another absorber of carbon dioxide, as Lord Tanlaw suggested, is the biosphere, consisting of all living matter on land and in the seas; consisting of the forests, which form the largest mass of the biosphere and which in the past were taking the carbon out of the atmosphere and should have been growing more abundantly because of the increased carbon developing. However, we are cutting them down and therefore the carbon is not being absorbed in that way. Thus, whatever the system of withdrawal—the sea or the natural vegetation—it has already been smothered. I have been reckoning today that it will take 1,000 years just to reduce to not even one half the amount of carbon now in the atmosphere to a balance between the oceans and the biosphere. In other words, the carbon is accumulating, and that is really all I am trying to say.

I should point out that man's activities operate in other ways as well. Part of the glasshouse effect is due to nitrous oxide which is due to the use of artificial fertilisers, and that is becoming a very serious problem as a contributory factor to the glasshouse effect. Let us consider what are the effects of higher concentrations of carbon dioxide resulting from this—on the analogy with the glasshouse—"greenhouse" effect. Carbon dioxide is a translucent layer, if you like, which admits the sun's rays but does not allow the surface heating of the earth to escape, so, as Lord Tanlaw pointed out, we get a natural warming up in the vapour sense of the word and we also get convection heat from the surface of the earth to the point where that begins to have real effects. Many theoretical calculations based on detailed observations have been made and they converge on roughly the same conclusion.

I apologise to noble Lords for making these technical points, but I was queried about them before I spoke and I feel I must put them on the record. The present 325 parts per million by volume (ppmv) of carbon dioxide in the atmosphere will increase to 400 ppmv by the year 2000. This will mean an average surface warming of 1 per cent.—that is the most conservative estimate—and only 50 years beyond that, by the year 2050, it will increase to 650 ppmv, which is a doubling, an increase in temperature of a minimum of 3 degrees Celsius.

I assure the House that I am talking in limited terms. I remind noble Lords that I am talking about the mean, the average, temperature of the whole globe, not local temperatures. This means that in the Polar regions the increase can be three to five times greater than the global average. The resulting reduced difference between the low and middle latitudes will be significant because it is the temperature difference between the Equator and the Poles which drives the atmospheric heat-engine. There will be a slowing down of the large-scale flow patterns in the air and in the oceans that transport the heat polewards.

We now come to what might be considered the 64,000 dollar—we might as well call it the 6,000 million dollar—question; namely, what happens to the ice caps? The ice can be represented in ice dams, which can be found in the Himalayas, the High Andes and elsewhere, and they can be represented by the glaciers, mountain glaciers and the permafrost. The biggest problem, however, we are dealing with is what will happen to the ice caps and the ice-sheets.

The melting of the sea ice would not affect the sea level because (Eureka!) the volume of floating ice is equal to the water it displaces. The melting of the glaciers and the ice caps on land, however, will raise the sea level. One of my minor nightmares is wondering what will happen to the ice- dams if they melt; I am talking about the glaciers and ice caps on land. If all the glaciers melted, the sea level would rise about half a metre, approximately .6 metres. If all the ice-sheets melted, the level would rise 65 metres. Anybody with property below 300 ft. should get rid of it. But that would be a deferred possibility because the warmed-up atmosphere would hold more vapour and that would increase the snowfall over the ice-sheets. All this is predictable—this is not something we are discussing as a remote possibility—within the next 70 to 80 years, within the lifetime at least of my grandchildren. It is therefore something we must deal with. It does not matter how we look at this issue—whether we take Dr. Mason's optimistic view about the way in which we may be increasing the potential for production and so on, or whether we take a grim view, or even whether we decide to cut off all coal and oil (just stop it altogether, which of course is completely unrealistic)—whichever way we turn, we seem to be in a jam because if we cut off the carbon going into the atmosphere we should then have an awful lot of nuclear waste. I hope that in the coming 70 years or so we will have fusion energy, but in the meantime things are going to be accumulating in the way I have described.

As the noble Lord, Lord Tanlaw, said, this is not something we can discuss in a quiet non-political way because it is a totally global political question, though it is not a political question which can be dealt with by "demos" or "sit-ins" or any similar ways. I reassure my noble friend the Minister that I do not see us marching to Bracknell on a sort of CND march saying, "Stop the weather". But we must sit down now, as we hope we are doing, and look at it in its totality, in its global sense; and if there is one thing that must unify mankind, scientifically speaking, it is this.

Lord JACQUES

My Lords, may I ask my noble friend whether he has had a depressing day? I ask this because when I listened to him on the radio this morning he said that the waters were likely to rise in the next 50 to 100 years by 60 metres—that is about 200 ft.—and that if one had property of less than 200 ft. one should move away from it, or not take the lease if it was for 99 years or thereabouts. However, during the debate he spoke of 300 ft., and so I was wondering whether he had had a depressing day.

Lord RITCHIE-CALDER

My Lords, as the ex-chairman of the Metrication Board I find it very difficult to convert metres into feet. The figure is 65 metres, whatever one may make that.

6 p.m.

Lord SKELMERSDALE

My Lords, it is always with some diffidence that a mere amateur follows a scientist in one of your Lordships' debates, but I am especially grateful both to the noble Lord, Lord Tanlaw, for introducing this very important subject, and for the dexterous way in which my noble colleague on the EEC Sub-Committee G on the environment has enlightened us with the true scientific facts behind this very complicated and very urgent question. Both the noble Lord, Lord Tanlaw, and my noble friend Lord O'Hagan said (if I may paraphrase slightly) that something strange is going on. The noble Lord, Lord Ritchie-Calder, said that something strange and serious is going on. I should like to reiterate all three views. I am absolutely convinced that something strange is going on. It is something serious that is going on, and we should be worried about it. The only problem is, how and what? I am not a reader of detective stories, but I can recognise that here we have a riddle of the "Did she fall, or was she pushed?" variety. We are being bombarded with a dichotomy of views and opinions. Hardly a month goes by without another eminent scientist publishing a paper leading to one or other view. It seems to me that the picture is so unclear that all anyone can do is to hold a watching brief on the subject of carbon dioxide and its relation to climate.

However, there are a few facts that we do know. The first is that carbon dioxide in the atmosphere is in the order of .03 per cent. and is increasing at the rate of some 10 per cent. per year, through the burning of fossil fuels, and, we must not forget, the large-scale plundering of the world's forest reserves which gave rise to these fossil fuels.

Secondly, the optimum level of carbon dioxide for photosynthesis is 0.1 per cent. This is important, as I hope to be able to show your Lordships. So we still have a little way to go before this point is reached. If I understood correctly the noble Lord who has just spoken, it will be about three quarters of the way through the next century. This sounds an awful long time away, but it is not, as I am sure the noble Lord will be the first to agree with me. This is a matter which we want to watch, and watch carefully, from this moment on, and I am delighted that there is to be a conference next year in Geneva. The conference will not exactly set the ball rolling—because it is already rolling, though very slowly—but it will give it a much needed push. Third in my list of facts is that carbon dioxide in the atmosphere absorbs radiation—the well-known greenhouse effect—and warms it, possibly (I say possibly) giving rise to the melting of the Polar ice caps.

What conclusions can we draw from these three facts? As I have said, I am not a scientist. I approach the matter in, I hope, a thinking amateur fashion; nevertheless, I approach it with great diffidence. I should have thought that the first conclusion is fairly straightforward and obvious. This is that the more we cut down forests, especially the tropical rain forests, the less carbon dioxide will be stored in the earth, either in the form of timber, which is a temporary stage, or in the eventual form of peat, and one would hope also that fossil fuels are continuing to be laid down, though I have not seen any reference to this recently in the Press.

Next is a rather more difficult conclusion, and it is here that the scientists have two possible theories. On the one side is the idea that the extra heat in the atmosphere will warm the oceans and melt the ice caps, but no one knows by how much. This will have the effects that it will increase the level of the sea, changing coastlines all over the world, putting many low-lying areas under water, as has already been referred to. However, it should not be forgotten that the oceans of the world are by far the largest reservoir of carbon, from carbon dioxide, that there is. So if the volume of the ocean and its temperature is increased, I should have thought—not being a scientist—that this would also increase its absorption capacity. I see a shake of the head, so I am obviously talking nonsense, but I am grateful to be told so.

We now come to the other side of the coin. Some scientists whose views I have read believe that far from the greenhouse effect to which I have already referred, more and more carbon dioxide in the atmosphere leads to the blocking of some of the suns's rays to the earth, and by dust and cloud formations will lead eventually not to increased heat on the earth, but increased ice. A book entitled The Weather Machine, published three years ago, painted a very gloomy picture of the effects and the causes of a possible new ice age into which we may, or may not, be entering. One must somehow receive a balanced view from two totally opposing scientific streams. We all know that there is an increasing level of carbon dioxide in the atmosphere, but we do not know what the effects will be. Incidentally, it occurs to me that in primordial times, when the land mass was chiefly covered with forest, but before much, if any, coal and oil was created, the percentage of carbon dioxide in the atmosphere must have been very much higher than it is now and will probably become in my life time.

Where has all this carbon gone? It must have gone into humus and peat, and into fossil fuels certainly—but this is only a very small percentage. Most of it must have gone into the sea. So far as I know, there is nowhere else for it to have gone. So I feel that the sea must be the key to the whole of this problem, and it is here that we must look for most of the answers.

It is critical that we discover whether it is getting warmer or colder, by how much, and over what length of time. It is not yet by any means certain that the overall result of warming, or indeed of cooling, would be as damaging as is usually assumed. The noble Lord, Lord Tanlaw, referred to Mr. Morgan's comments in last week's edition of the magazine Nature in which he said that a rise of 2 to 3 degrees Centigrade might well lead to increased food production by prolonging the growing seasons, increasing the rainfall, and increasing photosynthesis. I suppose that the converse of this argument might well be that a fall by the same amount could well do the same by shrinking the deserts and thus making more land available for food production. So I do not know where I stand.

I am most grateful that this Question by the noble Lord, Lord Tanlaw, is on the Order Paper today, and that we can discuss it. However, I am convinced in my own mind that neither Her Majesty's Government, nor anyone else, can in fact answer it. I should like to ask the Minister whether she can give us an assurance that she and her Department—or the Ministry of Agriculture, Fisheries and Food, or, as my noble friend Lord O'Hagan asked, whichever is the supremo Department on this subject—are extremely concerned by the problem and are watching it closely; and secondly, that they will do all in their power to make sure that the leaf cover of the world—another of the problems—although changed by advances in agriculture, should be maintained. If the noble Baroness is again offering us a space to watch, I assure her that I shall watch it with assiduity.

6.9 p.m.

Lord GISBOROUGH

My Lords, I should like to intervene in the debate briefly to draw particular attention to the forestry aspect of this matter. The debate cannot but remind one of those debates on energy a few years ago, when people started to suggest that one day there might be an oil shortage, or even an oil crisis. Within a short time it was with us with a vengeance. Since 1850 human activity has increased the amount of carbon dioxide in the atmosphere from perhaps 290 to 330 parts per million. By the year 2020, or thereabouts, the amount of carbon dioxide in the atmosphere could be doubled. Until recently this was largely attributed—indeed, it was in this debate—to the burning of fossil fuels. Evidence now points to the fact that it could in equal degree be due to the destruction of forests. There are a great number of studies being made, each reaching a different result and none of them being conclusive; and what I am saying is based on one of those studies.

It is important—indeed, it is vital—that an accurate assessment be obtained for the world's safety. Should the felling of the world's forestry reach a conclusive state, then it may be too late to counteract it. One study showed that tropical rain forests hold 42 per cent. of all carbon locked up in terrestrial vegetation and account for 32 per cent. of total net primary production. All forests hold some 90 per cent. of carbon and contribute 60 per cent. of production, according to that same study. These figures lie about half-way between the extreme estimates. Over the last 1,000 years forestry cover in Western Europe has been reduced from about 90 per cent. to 20 per cent., and this reduction released a quantity of carbon that formed a significant fraction of the total previously held in the atmosphere. It is reasonable to assume that continued industrialisation and population growth since 1900 has resulted in similar changes in forestry elsewhere.

In New England the reduction of forests occurred since the arrival of the settlers, but since 1900 there has been a period of recovery owing to the abandonment of agriculture and the expansion of forestry into the former agricultural land. The recovery, however, has not resulted in a pool of carbon equivalent to that of the original forests. Regular harvesting has never allowed the forests to reach the stature and extent of the original ones, so that the standing crop of carbon today is no more than half the original one. Furthermore, the increase of forestry has now ended due to a renewed expansion of agriculture and an intensified harvesting of trees. The experience of the New England study suggests that the regrowth of forests in temperate zones probably does not at present provide a large sink for atmospheric carbon dioxide.

Meanwhile, there is a continuous expansion of argiculture into other forest lands, a continuous harvesting of primary forests elsewhere, and a general toxification of the earth as a result of human activity, particularly in the tropics. The largest remaining forest area is of course the Amazon Basin, and there is no satisfactory survey giving accurate data of the destruction of forests in that important area. It is difficult to avoid the conclusion that the destruction of forests is adding carbon dioxide to the atmosphere at a rate comparable to the rate of release from the combustion of fossil fuels, and, if oxidisation of humus is included, at an appreciably higher rate. This is a highly complicated and technical subject with inadequate scientific conclusions. The important point is that when the effects of deforestation become evident it may then be too late to make redress.

If the greenhouse effect were to occur, perhaps the world would be a warmer and pleasanter place in which to live. Perhaps deserts would become fertile with rains. Perhaps, however, the ice floes will melt, and the ensuing floods will perhaps cause, with respect, the Lord Chancellor's Procession along the corridors to be made in a caparisoned and emblazoned gondola propelled, perhaps, by a gay and gallant gondolieri in the form of Black Rod with a long black rod. Whatever the future, the world should try to understand the consequences of its actions in this field of nature, so that remedy may be taken before it becomes too late to escape the consequences.

6.15 p.m.

The PARLIAMENTARY UNDER-SECRETARY of STATE, DEPARTMENT of the ENVIRONMENT (Baroness Birk)

My Lords, the noble Lord, Lord Tanlaw, has certainly raised a question of truly global concern, and it is quite clear that this short debate has been extremely important and very interesting. It was also very scientific. I do not know about the deluge of ice or heat, but I have certainly never had such a deluge of paper around me to help fill in the tremendous blocks of ignorance from which I suffer on this subject. The Question that Lord Tanlaw has asked, if I may come back to that—because we have ranged fairly widely—is, whether there is cause for concern in the current increase in atmospheric carbon dioxide and apparent change in global weather patterns". Before I get on to the Answer, which I believe is scientifically-based and is as accurate as I can give your Lordships, I must confess that I share the feelings of noble Lords—and I think the noble Lord, Lord Skelmersdale, summed it up—that something strange is going on. I have my own private, pet theory that none of this radioactivity does us any good at all and does the weather a lot of harm, but I do not know that I have the scientists on my side in that respect so I think that that had better be in parenthesis.

In summary, the Answer to the Question asked by Lord Tanlaw is that the increase in CO2 that is occurring certainly gives grounds for concern because it can without doubt affect the world's climate. It is too early to say, however, whether the climate is in fact being affected, because there is no sufficiently long-term firm evidence. I know that my noble friend Lord Ritchie-Calder takes a different view, but the view we take is that any effect will be very gradual indeed, spreading over decades, and will certainly give us time for further research into the question on which some of the world's most able scientists are working. I shall be saying a little more about research later. Our own Meteorological Office is taking a leading part in this research. The noble Lord, Lord Tanlaw, asked me whether there was any inter-Departmental liaison, or any committees. An Inter-Departmental Liaison Committee was set up in 1977, and to the best of my knowledge it covers the Departments of Environment, Energy and Defence, and the Meteorological Office is giving scientific leadership in research by meteorologists and climatologists.

The subject of carbon dioxide and its potential impact on climate is surrounded both by uncertainties and by scientific controversy, and that was made very clear in the extraordinarily interesting contribution from my noble friend Lord Ritchie-Calder. What is clear is that CO2 concentrations in the atmosphere are steadily increasing, as they have been doing since the mid-19th century. The chief reasons for this rise are, as noble Lords are aware and as some noble Lords have mentioned, the increasing global use of fossil fuels and the destruction of forests, particularly tropical forests—and the noble Lord, Lord Gisborough, mentioned that just now—although it is not clear what are the relative contributions of fuel burning and forest clearance. During this century, the carbon dioxide concentration has increased about 10 per cent. The noble Lord, Lord Skelmersdale, said (it may have been a slip of the tongue) that he understood the increase was 10 per cent. per annum. It has been 10 per cent. over the century. It is nearer about one-half of 1 per cent. per annum.

My Lords, I am not going to go into a long explanation of the greenhouse effect, which is obviously common knowledge among all the noble Lords who have spoken and who have explained it, as Lord Tanlaw did originally, extremely well and clearly. But mathematical models of the world's climate suggest that this greenhouse effect could significantly raise the temperature of the lower atmosphere and the earth. Such a rise in temperature, although I agree that in many respects it could be very pleasant for us personally, particularly if, like myself, one is cold most of the time, could be of major importance to the global climate, affecting not only the average global temperatures but also rainfall, winds and the ocean currents.

During the debate, noble Lords have mentioned various figures for future CO2 levels; but what those atmospheric levels will be, and at what levels significant effects are likely are not questions we can yet answer with confidence. One reason for uncertainty is that, although we know that the oceans and living things absorb some of the CO2 produced, we do not know enough about the carbon cycle to say how much will be absorbed. In answer to the question that the noble Lord, Lord Tanlaw, put to me, there is no certainty about the future level of CO2, but most estimates, at their worst, predict a doubling in 50 years. However, estimates have been made that the increase may be from 330 parts per million now to 370 ppm to 385 ppm by the year 2000 and 450 ppm to 620 ppm by the year 2030. That is, perhaps a 50 per cent. to 100 per cent. increase in 50 years.

What effect will all this have on the world's climate? There have been a range of predictions by noble Lords and what I will be saying is based on the best scientific advice available to the Government through the Meteorological Office. Here again the answer is not yet known. Mathematical models have been developed to predict the possible changes; but they are not able to allow for factors which may work to stabilise the climate. For example, it has been suggested that a small increase in global cloud cover could block out sufficient solar radiation to balance the enhanced heat retention of the atmosphere. Also, the circulation patterns of the oceans may alter to compensate for the temperature rise. It is, therefore, unclear whether the increase in carbon dioxide would actually have the greenhouse effect predicted.

In answer to another question raised by the noble Lord, Lord Tanlaw, it is most unlikely that weather conditions affected by CO2 will probably have any effect before the end of the century when some effects will begin to be noticeable. But before that, they would be unlikely to be noticeable over and above the normal fluctuations of our weather. Nevertheless, predictions have been made that a doubling of the level of CO2 in the atmosphere could raise the global temperature by about 1.52 degrees Centigrade to 3 degrees Centigrade. At the lower end of the forecast of CO2 increase that I have just quoted, a 50 per cent, increase might lead to a 1 degree Centigrade rise in 50 years. It has been suggested that any effect may be measurable by the year 2000; that is, we may by then be able to distinguish the effects of the increase in CO2 from the natural fluctuations that are always taking place in the world's climate.

The noble Lord, Lord Tanlaw, raised the question of why we were not able to predict the drought. The drought in 1976 was part of the natural variability of climate—which is rather different from long-term changes. This was not known beforehand and predictions are certainly not that good even on a one-month basis. Even if one had created a Minister for Droughts, one is not creating another God; so that one could not do anything to stop it. One was dealing with the situation when it arose, trying not to panic people or to put the country to enormous expense unless it was necessary. I think the noble Lord would agree that this is rather different from the long-range viewpoint.

Lord TANLAW

My Lords, I thank the noble Baroness for giving way. The reason why I raised the question was that the rainfall during the winter months was (I think) 50 per cent. below the average; in which case it goes without saying that it was impossible for that rainfall to be made up during the summer months. There was a guaranteed drought as soon as it was known that the winter rainfall was 50 per cent. below normal. This is why the Government should have been told of this rather basic fact of meteorology and given some forewarning to the councils about the future drought which was inevitable.

Baroness BIRK

My Lords, I appreciate that, because I was standing at this Box, answering many questions and putting forward Government policy, during the period of the drought. These things are very difficult and I think they relied on the wet summers which so often follow dry winters. But I am not going to pursue that further. I have come to the end of my knowledge on that. But I will certainly pass on his thoughts and, in any case, they will be recorded in Hansard.

My noble friend Lord Ritchie-Calder mentioned the question of the Gulf Stream moving south; but there does not appear to be evidence that it has moved south to any significant degree. The trouble is that there are too many unknown factors for prediction to be made with certainty. All that we can talk about are the trends, being careful that we are keeping a watch on them and putting the input into the research that is necessary. The indications are that we might expect the "worst possible case" of a 2.5 degree Centigrade rise in temperature by the year 2030 to begin to have an effect on United Kingdom agriculture. The noble Lord, Lord O'Hagan, mentioned the question of crops of barley. Certainly some regions and crops would benefit from the longer growing season, although others, such as cereals, might begin to suffer.

It is not clear what would happen to rainfall in such circumstances. There could be a sizeable increase or decrease, both of which could have major implications. A 2.5 degree Centigrade temperature rise might also result in sea levels rising. But, if this did occur, this is thought likely to be by less than 1 metre, on average, which could increase the risk of flooding in low-lying areas only.

Speculations about the Antarctic glaciers melting and raising sea levels 5 metres or more and about the Sahara and Arabian deserts being restored to fertility are, I think, centuries rather than decades away and really come into the field of futurology. Such eventualities are not only remote in time; they are highly conjectural. That does not mean that we should not be considering them now—although I do not know what species may be on earth if the earth is covered in water. When I say "we" I am talking about our successors whoever and wherever they may be. They may be looking at it all from a different planet. But that does not absolve us from the responsibility of doing what we can at the present time.

Before the effects become significant, we should have had time to extend our understanding of climate and climatic disturbance by research. I think that this very timely nudge to the Government and to people generally is extremely welcome. Research into climatology is a major growth area among the world's scientists. I, like most noble Lords, saw last week's issue of Nature, with its full supplement on climatology. Britain is in the forefront of world climatological research. The development of climate simulation models (which was raised by the noble Lord, Lord O'Hagan) requires scientific resources and computing power that is currently available only in the USA and the British Meteorological Office. The Meteorological Office research has been expanding steadily over the last 15 years and has made remarkable progress in modelling the global climate.

When my noble friend Lord Ritchie-Calder asked why this subject was in the domain of defence, I was not disagreeing with him, but saying that that is what I, too, wanted to know. It is a question that I had asked. I understand that it is for historical reasons. The Meteorological Office was set up by the Admiralty in the 19th century to forecast gales and weather for shipping. Whether noble Lords feel that the time has come for this to be reviewed, I do not know; but it seems to me, speaking off the cuff, the time may have come for us to look at this. It was only on the basis that defence was not really an issue in the Unstarred Question of the noble Lord, Lord Tanlaw, that, Environment being the nearest Department to the weather, I am here answering this very difficult Question. If only the noble Lord, Lord Tanlaw, had brought in a question which was something to do with defence—and I must say I tried to persuade him but he was not having any of it—he would have had somebody else replying. It is quite as chancy as that.

Lord DAVIES of LEEK

You are doing all right, do not worry!

Baroness BIRK

My Lords, within the climatology research branch of 33, costing £740,000 a year, there are 17 people at the Meteorological Office directly concerned with developing and experimenting with climate models at an annual cost of £380,000, a substantial part of which relates to work on carbon dioxide and its effects. There are plans to increase the computing power available so that work, particularly that relating to CO2, can be pursued more effectively. Whether that is a right and proper use of our resources, I frankly do not know. We have to recognise the other priorities and demands on research resources. I agree it is something we must keep an eye on all the time and, if necessary, divert more research to it. The noble Lord, Lord O'Hagan, mentioned the CPRS. Sir Kenneth Berrill has taken a great interest in this subject and it is not lost on them. I do not think I can say any more on that at the moment.

Internationally, research is being promoted by the World Meteorological Organisation, the International Council of Scientific Unions and the United Nations Environment Programme, and a World Climate Programme 1980–2000, sponsored by the World Meteorological Organisation and the ICSU, is being launched with a major world climate conference in Geneva in February 1979. This is extremely good news because this means that there will be a great deal of publicity and discussion on this very important subject.

The United Kingdom plays a full part in promoting and contributing to this international research effort as well as carrying on our research at home. There is also considerable interest, as I am sure the noble Lord, Lord O'Hagan, is aware, in this research in Europe. The Commission of the European Communities has submitted proposals for a new programme of climatology research which will include carbon dioxide and its effect. This proposal is at its early stages, and discussions on it are proceeding. I cannot see any harmonisation problems arising yet on that.

The noble Lord, Lord O'Hagan, asked me about the cost of this. The programme, if agreed, will cost £5.4 million over five years. Research into this global question, as has been pointed out by the noble Lord, Lord Tanlaw, and particularly by my noble friend Lord Ritchie-Calder, is of international concern. I entirely agree that it is also a political question in the widest sense, just as international co-operation will be of crucial importance in any action which may prove to be desirable either to control the increase in CO2 concentrations or to accommodate the climatic changes that are predicted. Therefore, without international cooperation we are not going to be able to come to grips with this problem in its global dimension.

If it becomes apparent that undesirable changes in world climate are likely, there may be important implications for energy policy and the future of coal as a source of energy. But it is too early to say what these implications may be. The United Kingdom would not, acting alone, expect to affect the global concentrations of carbon dioxide, and our own energy policy is designed to retain a mix of energy sources and avoid excessive reliance on any one source precisely so that we can respond to future changes that we cannot always foresee accurately. I took particular note of what the noble Lord, Lord Gisborough, said about the effects on forests, and I have also commented that lack of forests can affect the climate.

I should like to point out to the noble Lord, Lord Tanlaw, that the Green Paper on energy problems refers to CO2 in chapter 12 on environmental considerations. The present state of this problem indicates that we have sufficient time to seek a better understanding of the possible effects of increasing CO2 in the atmosphere before the time arises when action may be needed. This does not mean that we should approach this question with complacency, which is what my noble friend Lord Ritchie-Calder is most concerned about. So far as the present resources allow and the present set-up in this field is concerned, I can assure your Lordships that the United Kingdom are fully involved, both at home and in international efforts, to increase our knowledge.