Climate Prediction Model
1
Chapter 3
Climate prediction model
Chapter 3
Climate prediction model
1.Purpose
2.The advancement of science
2.1.Journal policies
3.Benchmark publications
4.1970: Commission of Enquiry into Water Matters
4.1.Extracts from Chapter 10 of the commission’s report
5.1978: Long range prediction of river flow
6.1995: Floods, droughts and climate change
7.1999: Risk and society
8.2001: An agnostic view
8.1.SAJS papers
8.2.My response
9.2002: Climate and the properties of rainfall and river flow
10.2004: Climate change – there is no need for concern
11.July 2004: The last roundup
11.1.Basic truths
11.2.Cornelius and Nel (2004)
11.3.Bredenkamp (2000)
11.4.Tyson (1987)
11.5.Interpretation of Table 2
11.6.Beyond all doubt
11.7.Western Cape
11.8.What now?
11.9.Finally
12.The tide turned
13.The journey so far
14.My Eureka experience
15.2005: Multi-year climate prediction model
15.1.1950 Hurst’s Ghost
15.2.Alexander 2001 to 2004
15.3.The prediction model
15.4.Interpretation
16.Summary and conclusions
17.My publications
18.References
1.Purpose
My climate prediction model is a world first. It took me 35 years to develop the model to the point where it can be applied in practice for planning purposes. The details are contained in my recently published paper Development of a multi-year climate prediction model (Water SA Vol. 31 No2. April 2005). I have included the manuscript version in Appendix E of this report.
By a strange twist of fate, the publication of this paper by the Water Research Commission marks the fulfilment of the two principal research-related recommendations in the report of the Commission of Enquiry into Water Matters published in 1970. These were the need to establish a coordinating body for water research that led to the establishment of the Water Research Commission (WRC), and the strong recommendation that a long-range climate prediction model, however coarse, be developed. These two recommendations have now been fulfilled by the publication of my paper in the first fully online edition of the WRC’s scientific journal..
Rather than restricting this chapter to the dry details of the model itself, I decided to recount the long and often difficult road that led to this point, including some occasions when I nearly threw in the towel. It is with some hesitance that I describe the unpleasant experiences, particularly the editorial policy of The South African Journal of Science, one of South Africa’s leading multidisciplinary journals, but these have to be endured and overcome in the interests of the advancement of science. I hope that they may provide some guidance to younger researchers who face similar difficulties in future, particularly in the field of interdisciplinary studies.
2.The advancement of science
2.1.Journal policies
Civil engineering is the oldest of all the professions. From the moment that you step out of your door you will see the work of civil engineers. Every structure has its civil engineering component. Many of them are invisible such as water supply, stormwater drainage and sewage disposal systems. Others are unmistakable such as the communication systems including roads, railways and airports. Then there are the large dams, canals, tunnels, reservoirs and pipelines than bring potable water into our homes. Each and every one of these components is based on the application of observational theory in the first instance.
The advancement of knowledge in the engineering journals was not only the publication of refereed papers, but equally important were the supplementary comments by others on the papers. Editors encouraged the submission of responses for which deadlines were published with the original paper. Occasionally the space occupied by the responses in a subsequent issue exceeded that of the original paper.
Two of my refereed papers in civil engineering journals were awarded prizes for the best paper of the year. They were Mortar intrusion concrete published in the Transactions of the SA Institute of Civil Engineers in October 1960, and Lessions learnt from the 1981 Laingsburg flood published in The Civil Engineer in South Africa in January 1982.
A similar policy was adopted in overseas journals in the related fields.
Unfortunately, this policy is not followed in journals such as the South African Journal of Science (SAJS), where responses are seldom published, and critical comments are rejected. As I will show later in this chapter, this policy has serious adverse effects on the advancement of interdisciplinary science.
This is a simple example. The major problem facing tens of millions of people on the African continent are poverty, malnutrition and disease. They have no defence against the occurrence of natural disasters, particularly floods and droughts. Also, due to poverty and overpopulation, the natural environment has become seriously degraded. There are three major interlinking issues: poverty – natural disasters – environmental degradation. These are described in Appendix A.
The March/April 2001 issue of the SAJS was devoted to Regional environmental change: multidisciplinary synthesis from southern Africa. Readers were informed that studies of global environmental change had become to occupy a central place in modern science, and the recognition that humans are to blame for global warming. Who are these humans? Are they the millions of people sitting around fires at night from the destruction of the natural vegetation for firewood? Next time you take the night flight to Europe during the winter months, look out of the window. You will be surprised by the extensive twinkling fires, as the local farmers prepare their lands for the spring rains. The atmospheric effects of these extensive veld burning practices have already been reported in the scientific literature. Will these activities also be prohibited if environmentalists and climatologists have their way?
Do the editor and authors expect us to believe that global environmental change and not poverty, malnutrition and disease pose the greatest threat to humanity? Most importantly, why do those of us with balanced views have so much difficulty in getting our material published so that the readers and the public can be presented with opposing views? Is this good science? I will discuss my experiences later in this chapter.
But let me begin at the beginning.
3.Benchmark publications
There are four benchmark publications that are directly relevant to the development of my climate prediction model.
The first is the Report of the Commission of Enquiry into Water Matters published by the Government Printer in 1970 (Appendix B). The second is my technical report Long range prediction of river flow: a preliminary assessment published by the Department of Water Affairs in 1978 (Appendix C). The third is my paper Floods, droughts and climate change published by the SAJS in August 1995 (Appendix D). The fourth is my recently published paper Development of a multi-year climate prediction model published by Water SA in April 2005 (Appendix E).
I deal extensively with these benchmark publications in this chapter.
4.1970: Commission of Enquiry into Water Matters
The Commission of Enquiry into Water Matters was appointed by the State President in terms of the Government Gazette No. 1480 of 1st July, 1966. Its terms of reference included the instruction to inquire into, to report upon and to submit recommendations on all aspects of water provision and utilisation within the Republic.
The following findings are directly relevant to this technical report.
(19) Forecasting of climatological conditions
Very great advantages in the management and practical utilisation of our water resources would follow if a measure of reliability could be achieved in the long-term forecasting of climatological conditions. If rainfall for a year ahead could be predicted with some certainty, advanced decisions could be taken with the result that the available water resources could be more efficiently utilised.
For some time past, attempts have been made to establish a correlation between rainfall and sunspot cycles, but in South Africa there seems to be little connection between sunspot activity, or changes in the intensity of sunspot activity, and rainfall.
The Commission regards it is essential that research and attempts to acquire the necessary data to make long-term weather forecasting possible be actively supported.
(31) Research
In the light of new developments in water technology, water research will undoubtedly play a key role in the optimum utilisation of the Republic's water resources. In view of the key importance and interdisciplinary requirements of water research, the Commission deems it essential that a specific committee for water research be established and that care be taken to ensure that the work of this committee be properly integrated with that of the Standing Committee for Water Affairs.
[This recommendation led to the establishment of the Water Research Commission.]
In view of the particular interest to of the Department of Water Affairs in water research a branch of the Department should be expanded to undertake, besides his own research, liaison with other scientific investigators and researchers in all fields affecting water supply.
[This was my responsibility when I was appointed as Manager: Scientific Services in the Department.]
4.1.Extracts from Chapter 10 of the commission’s report
The following terse extracts form Chapter 10 of the commission’s report (Appendix B) are very important as they reflect the position as it was 35 years ago and the foresight of the commission’s members.
- The possible value of long-range weather forecasting to planned water utilisation is thus of deep concern.
- One of the foremost achievements of the new century would be to forecast well in advance the incidence of famine in India or drought in Australia by means of analyses of sun-spot spectra.
- Also to be emphasised is the fact that long-range weather forecasting is affected by long-term climatic fluctuations. Although these are receiving considerable attention, progress in this direction is hindered by lack of reliable data.
- Assessment of a specific technique must be based on results of observations extending over many years.
- Successes achieved in long-range forecasting will be a measure of the progress being made towards ultimate solution of the problem of the general atmospheric circulation.
- The ability to forecast for one or more seasons in advance is within reach of the present generation.
- Some meteorological conditions exhibit the tendency to persist longer than might be expected as a matter of chance and use may be made of this tendency to venture a forecast
- The drought phenomenon remains one of the country's most vexing problems and it is in drought prediction that long-term forecasting can probably be of the greatest value. On the other hand, it must be admitted that meteorologists have not yet succeeded in discovering the fundamental causative factors either of drought or of excessive precipitation. The classical attitude, viz. that drought is purely a chance occurrence in the climatic history of the country does not appear to be correct. In an objective approach the possible influence exerted by fluctuations in the sun's radiant energy on the incidence of drought is stressed. Some of South Africa's most severe and prolonged droughts of the nineteenth and twentieth centuries have without doubt coincided with troughs of minimum sun-spot activity. The sun thus appears to be either directly or indirectly responsible for abnormal weather. As the exact mechanism is not yet clear, research in this field should evidently receive earnest attention.
- 7. Research
- Whatever the current status and reliability of long-range weather forecasting, the Commission is convinced that very serious consideration will have to be given to a purposeful attack on the problem. The results of long-range forecasts, while in the experimental stage, need not necessarily be made known to the public but can well serve as a supplementary guide in planning the utilisation of water supplies. The Commission is of the opinion that the Department of Water Affairs should promote the relevant research in co-operation with the Weather Bureau and other interested bodies.
- Long-range weather forecasts, even though approximate, can be of tremendous benefit in the management of water resources. Even were it possible to forecast that next year will be wetter or drier than usual, with perhaps some indication of the probable degree of departure from the mean, this would greatly aid the taking of decisions that might be of vital importance to the country's economy. [My emphases]
It is with pride and humility that I can announce that after 35 years I have achieved the objectives so clearly set out in the commission’s report.
5.1978: Long range prediction of river flow
A list of my publications and presentations on climate change related topics is given at the end of this chapter. My technical report Long range prediction of river flow – a preliminary assessment was the fourth of 76 publications and presentations that I produced on this and related subjects. It has occupied a good deal of my professional life. In passing note the wide variety of audiences that I addressed. This is the essence of efficient technology transfer. It is far more important than the publication of 5000-word refereed papers in the scientific journals that practitioners never read.
My technical report was published by the Department of Water Affairs in 1978. I have attached it in toto in Appendix C. I demonstrated that sudden periodic changes occur in most South African rivers. I wrote:
The purpose of the present assessment is to examine the records of river flow in South Africa in an attempt to ascertain whether they show a periodicity or correlation with sunspot phenomena that could be used as a predictive tool.
I concluded:
While there is some visual evidence of correlation between river flow and sunspot numbers, both phase and amplitude differences are too large for this relationship to be used for predictive purposes. The phase and amplitude of the sunspot cycles themselves are not accurately predictable which compounds the difficulty.
However, I continued my studies and observed the behaviour of annual flows in the Vaal River in particular. Over the following years it was fascinating to see the cumulative departure curve follow the pattern of previous sequences. The periodicity had not yet reached the 95% level of statistical significance but the signal was very clear. I developed a numerical simulation model, which I presented at several South African and overseas conferences. By 1993 I had presented another 39 publications, (numbers 5 to 43). I was very confident that the next reversal would occur within the next two years.
6.1995: Floods, droughts and climate change
I submitted my paper Floods, droughts and climate change to the SA Journal of Science in 1993. I predicted that the then current drought would be broken by severe floods within the next two years. This was based on the observed 20-year periodicity in the data, which later analyses showed it to be 21 years, and still more recently to 20,8 years. My manuscript version of the paper is reproduced in Appendix D.
For 18 months my faxes to the editor enquiring about my paper went unanswered. In April 1995 the IGBP organised an international conference here in Pretoria. I delivered my Floods, droughts and climate change presentation and informed the audience that the editor had not responded to my queries. I suggested that the editor was exercising his constitutional right to remain silent. One of the reviewers was in the audience and I was informed that the paper had been recommended for publication a year previously. I received a response from the editor within a week and the paper was published in the August issue of the journal.
At this stage I must emphasise that my differences with the editor were never a personal issue. He stuck to his guns and I stuck to mine. It is my perception that the editorial policy of the SA Journal of Science is not to publish controversial matter, particularly in the field of climate change. This is a pity, because I believe that the whole climate change issue has started to crumble internationally. The international studies have produced a massive amount of good research. When the Kyoto Protocol fails, as it must, it will result in a huge loss of public confidence in science and scientists. Editorial policies that refuse to publish opposing views must bear part of this responsibility.
Fulfilment of my prediction occurred within four months of the publication of my paper. In 1991-92 the worst drought on record in sub-Saharan Africa occurred, and 42 million people were affected. In November 1995 the drought was broken by the high seasonal rainfall in South Africa, Zimbabwe and Mozambique. There were some 500 deaths, 50000 homeless and US$ 200 million damage. Heavy rainfall occurred over large parts of South Africa from November 1995 onwards. In December, 157 people lost their lives in a flood near Pietermaritzburg – the highest loss of life in an urban area to date. In January, the Vaal River at Vaal Dam experienced the largest flood since the commencement of records more than a hundred years ago.
In my guest presentation to the Fifth International Conference on the Southern Hemisphere Meteorology and Oceanography held in Pretoria in April 1997 I informed the attendees:
The periodicity of these sudden changes in South African river flow, and the consequent frequent imposition of water restrictions, have been known for the past 25 years, but the difficulty was the lack of conclusive proof of the periodicity due to the shortness of the records of river flow.
An analysis of the inflow records for Vaal Dam up to September 1996, has at last provided conclusive proof of statistically significant 21-year periodicity (previously assumed to be 20-years), which is no longer in doubt.
There is also statistically significant periodicity in the rainfall over the Vaal Dam catchment. The inflows into other major South African dams show similar characteristics.
7.1999: Risk and society
In 1999 I was commissioned by the United Nations IDNDR to undertake a study that I titled Risk and Society - an African perspective. This is attached as Appendix A to this report. I discussed it in previous chapters.
8.2001: An agnostic view
In Chapter 1 above, I discussed the circumstances that led to my attendance of the Water and Climate workshop in Tokyo in June 2001, and the WMO’s objection to the draft report produced after the conference:
Water managers repeatedly pointed out that changes in climate of the magnitude currently being simulated by GCMs would easily be accommodated by the management decisions required for dealing with changes in population, land use and environmental regulation.