CYCLICAL BEHAVIOR C 



and ranging) needs further evaluation 

 and refinement. Similarly, routine 

 availability for grid-points of all data 

 collected by satellites is essential for 

 maximum climatological use of the 

 information. 



Adequate deployment (including 

 long-term satellite coverage) presents 

 the major problem. The number of 

 long-term "benchmark" stations for 

 measuring the variables referred to 

 earlier, in addition to the climatic 

 parameters, is inadequate for many 

 regions of the globe. 



Requirements for Scientific 

 Activity 



The present climatic fluctuation 

 may be of immediate economic signifi- 

 cance for areas with marginal climate, 

 especially in high latitudes. Over the 

 longer term, possible changes else- 

 where could be of major importance 

 for the planning of agricultural pro- 

 duction, architectural design, heating 

 requirements, and transportation sys- 

 tems. It may not be possible to fore- 

 cast climatic fluctuations with anv 

 confidence for a decade or more, if at 

 all, but any planning should incorpo- 

 rate the best advice of climatologists. 



Data Collection — Continued and 

 intensified monitoring of atmospheric 

 dust content, especially in mid-ocean 

 and high-elevation sites, is needed. 

 Satellite monitoring of global cloudi- 

 ness, snow and ice cover, atmospheric 

 vapor content, and sea-surface tem- 

 perature, with routine data reduction, 

 is also required. 



Data collection needs to be planned 

 to continue on a long-term basis, 

 through such programs as the Global 



Atmospheric Research Program and 

 the World Weather Watch. The per- 

 spective must certainly be global. (In 

 this connection, it is worth noting that 

 in much of tropical Africa basic data 

 networks are now seriously reduced 

 below what they were in the colonial 

 era, and this will greatly restrict 

 future analyses.) Planning for data 

 collection is urgent within the next 

 year or two. It cannot be stressed 

 too strongly that studies of climatic 

 change require a long series of 

 records. 



Data Analysis — Exhaustive analy- 

 sis of all available historical weather 

 information, especially outside Eu- 

 rope, is needed to provide perspective 

 on the recent period. Historians 

 could contribute significantly here. 

 The reliability of the data must be 

 assessed and it must be stored in a 

 form suitable for application of mod- 

 ern retrieval systems. 



Collection and synthesis of all 

 available "historical" information may 

 take twenty years. It will, however, 

 provide essential information for con- 

 tinued development of theory and 

 prediction, and it should serve as a 

 considerable stimulus to interdisci- 

 plinary work and exchange of ideas 

 in the fields that are concerned with, 

 or affected by, climatic change and 

 its implications. 



Dendroclimatic and snow/ice core 

 studies should be extended to supple- 

 ment direct records. Dendroclimato- 

 logical work in the tropics (Africa 

 and South America), especially near 

 the alpine timberline, is particularly 

 needed. 



Further study is needed of the mag- 

 nitude and spatial extent of fluctua- 



tions for different climatic parameters, 

 and of rates of change. These might 

 offer confirmation, or otherwise, of 

 the existence of various rhythms. 



Advances in general atmospheric- 

 circulation studies over the next dec- 

 ade should greatly improve our 

 understanding of the way in which 

 the atmosphere responds to internal 

 and external forcing functions. If 

 the present climatic deterioration in 

 middle and high latitudes of the 

 northern hemisphere is part of a 50- 

 to 100-year fluctuation, research over 

 the next decade would be critical in 

 terms of our "engineering" ability to 

 cope with it adequately. 



Finally, analyses of air-sea feedback 

 effects on various time-scales need to 

 be undertaken. 



Numerical Model Experiments — 

 Model experiments should provide 

 definitive information on the effect 

 of such variables as pack-ice extent, 

 snow cover, and sea-temperature 

 anomalies on the heat budget and on 

 atmospheric circulation patterns. Ade- 

 quate sophistication will probably be 

 available for this work within two to 

 five years. 



Work in progress should provide 

 information on tropical-temperature 

 and trans-equatorial links in the gen- 

 eral circulation necessary to an under- 

 standing of spatial aspects of fluctua- 

 tions. It is not yet clear, however, 

 whether or not this work will clarify 

 understanding of the way in which 

 seasonal weather patterns commonly 

 develop in different manners in differ- 

 ent years. This is fundamental to the 

 possibilities of predicting short- or 

 long-term fluctuations. 



Environmental Cyclic Behavior: The Evidence of Tree Rings and Pollen Profiles 



One of the major problems to be 

 faced before we can arrive at an un- 

 derstanding of environmental cyclic 

 behavior is concerned with standard- 



izing definitions. Attempts at world- 

 wide standardization of terms in cli- 

 matic studies are being made. The 

 Commission for Climatology of the 



World Meteorological Organization 

 has published two suggested glossa- 

 ries, one for various statistical charac- 

 teristics of climatic change and the 



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