Environmental Aspects: Distribution of Attention

A look at the way attention has been distributed by global models across different aspects of the environment (see Figure 7) shows that some of the most critical areas have largely been ignored while areas of lesser importance have been emphasized. Deforestation is the most prominent omission, and a needless one. No one has exact parameters on a global basis on forests, their rates of disappearance, and their role in protecting water- sheds, holding soil, fixing C 0 2 , and providing firewood; however, direction and order-of- magnitude estimates can be made. Likewise the connections between poverty and forest clearing and between fuel costs and firewood gathering are not easily reduced to simple mechanisms and estimable parameters. However, once again, enough is known to make

L

*-

-

//deforestation

\\

included 'OC

toxins

- - , I . and

pollurants

("World 2 and World 3;

UN World Model; SARUM)

FIGURE 7 Environmental coverage of global modeling to date (an asterisk ( * ) indicates a model in which the particular aspect is endogenous).

90 J. M. Robinson plausible guesses, and the process of making alternative guesses and observing the model's sensitivity to the parameters and mechanisms assumed would be valuable; it would lead to a better sense of what data are needed and of the costs that may be incurred by the poverty of our present knowledge of the global forestry situation, and, above all, it would prevent the dangerous assumption that the health of the biosphere is unaffected by wide- scale forest removals.

It is also significant that no global model has yet dealt explicitly with genetic sta- bility, oceans, or highly toxic materials, that only the WIM has attempted to deal with climatic change at all (and the WIM included only a simple index of CO, release through fuel combustion), and that the only treatment of soil degradation to date has been the simplistic globally aggregated treatment in World 3. In sum, natural biological and clima- tological systems are underdeveloped areas in global models.

By comparison, variables that are easily related to industrial activities - especially pollutant generation, reserve depletion and human services - have been given relatively comprehensive treatment; this observation would become stronger if more global models had been included. The pressure to include fuel-resource dynamics in global models has become very strong in the last few years and most recent models have given it great atten- tion. For example, GOL*, SARUM, and FUGI are all energy conscious and the Berlin (Wissenschaftzentrum) model is almost certain to look at petroleum-related conflicts.

SARUM also includes detailed treatment of pollution generation.

On balance it appears that global modeling has expanded extensively into rich people's environmental problems (pollution and depletion of mineral resources) while retreating from environmental problems such as deforestation and soil degradation which bear directly on the basic needs of the world's poor. Likewise it has expanded into questions of global ekonomic welfare while retreating from the question of biological and climatological health and stability.

In my opinion, in both scientific and humanitarian terms, the trend is a misallo- cation of resources. Scientifically the most interesting thing about early global models was their attempt to see the world's biotic and economic systems as an interacting whole.

It is disappointing to see the biota dropped from the picture. In humanitarian terms a blind eye is turned on a billion and more people whose subsistence depends on the sus- tained productivity of their fields, the reliability and cleanliness of their water supplies, and the availability of firewood and other biologically derived fuels. There is also a failure to look at the question of how the poor man's most available resource - human labor

- can be mobilized in the labor-intensive task of rebuilding damaged ecosystems and sustaining those that are now threatened.

There are some signs that the trend is turning. MOIRA 2 shows promise of provid- ing the basis of a scientifically sound and comprehensive treatment of the dynamics of global agricultural soils. MOIRA 2 could be extended to cover forestlands as well. Atten- tion is mounting on the CO, question, and research in that direction will require better accounting on a global basis for changes in the carbon content of soil and forest eco- systems. Given resolve and persistence in the next five or ten years global modeling could develop a credible scientific base for understanding the long-term interrelationships between human activities and the natural systems of our planet.

* GOL = the grains, oils, and livestock model of the US Department of Agriculture.

Treatment o f the environment in global models

REFERENCE

Barney, G.O. (Editor) (1979). Entering the 21st Century: Report of the Global 2000 Study to the President. US Government Printing Office, Washington, D.C.

DISCUSSION

Steger drew attention to the fact that many toxic substances in widespread use today may have extremely severe ecological impact if used over 25 or 50 years. Although their impact is not felt today it would be of the utmost necessity to include their effects in a global model reaching that far into the future.

In reply Robinson agreed that toxic substances definitely require proper attention;

still, it is even more important to reflect in the models issues of more immediate concern (like deforestation).

Driessen added that these problems are not independent: deforestation leads to a quicker accumulation of toxic salts in the topsoil, precluding the growing o f crops, at an estimated rate o f a hectare per minute. In the humid tropics the fertility of the soil is often lost owing to the fact that deforestation leads to erosion o f the topsoil and the sub- soil has a high level of aluminum which is toxic to crops.

Robinson said that it is a question of classification whether this problem should be regarded under the heading of "toxicity" or under "erosion': Parker opined that it should not prove too difficult to treat deforestation in a world model; in SARUMit could be done. Robinson added that "deforestation" is often regarded as "land development for agricultural use''; it depends crucially on the circumstances whether the positive or the negative side is justified.

Steger stressed the necessity to disaggregate geographically any treatment o f en- vironmental parameters; often the variations are just as important as the averages.

Robinson agreed fully;

if

Mesarovic suggested that one should differentiate between two types o f problems, both o f which deserve thorough research: one is the area of human impact on the en- vironment and the other is the ecological interrelationships themselves.

Parker expressed a word of warning concerning the expectations from a global model. It would be more than fallacious to judge a model according to whether it could answer any kind o f detailed question, from local deforestation to the eutrophication of a particular lake. Bruckmann replied that the historical development was the other way around: global models reflected environment too little, and it was generally felt to be desirable that global models should go more deeply into environmental questions than they had done in the past. Parker clarified that global models should certainly contain environmental considerations but, being "models", they should not overburden them- selves with details. For detailed studies special (not global) models should be used. In a global model it might suffice to treat environment exogenously, in the form of alternative scenarios.

92 J. M. Robinson

Mesarovic disagreed: it would be misleading to have, for example, a very detailed price-related trade economic model and a very detailed population model while ignoring issues like COz in the atmosphere. Bruckmann seconded this view: in the case o f both the Latin American model (Bariloche) and MOIRA, environment was practically excluded;

the exogenous environmental considerations made were generally overlooked by the readers.

Roberts asked Robinson how she thought that all these individual aspects of en- vironment could be incorporated into a global model. In reply Robinson reported an exercise done by the Global 2000 team, namely to cut existing linkages within well- known models (World 3, Mesarovic-Pestel, Leontief); without these linkages the models represented more or less official projections made independently from each other, while with the linkages the models showed considerably worse performance in terms of human needs. From this exercise it could be concluded that any additional linkage included (e.g. between deforestation and agricultural development) would yield a much more pessimistic outlook than those which all models without such linkages provide. Mesarovic gave an example underlining this view: the amount of coal that many models assumed to be used by 2030 might increase atmospheric COz by 69-1 00%, which would have strong ^. repercussions even on the energy options themselves. If this linkage were included in a model now it might influence energy policy at a much earlier date.

Kellogg added that the knowledge accumulated by the ecologists is far from satis- factory, for example, in deforestation. Robinson disagreed: dath available on ongoing developments, often alarming, in many parts of the world allow a fair estimate o f the order o f magnitude o f the parameters involved, sufficient to be incorporated in modeling work.