Freshwater Resources in Arid Lands (UNU, 1997, 94 p.): 6: Global warming and groundwater resources in arid lands: Conclusions

Freshwater Resources in Arid Lands (UNU, 1997, 94 p.)

(introduction...)

Preface

Opening address

(introduction...)

References

Welcoming address

(introduction...)

Reference

1: Fresh water - A scarce resource in arid lands

(introduction...)

Introduction

International efforts

Fresh water - A limited resource

A personal history

Traditional wisdom

Problems of major continental aquifers

The Aral crisis - Ecocide in arid lands

Hydropolitics along the Jordan river basin and the Dead Sea

Conclusions

References

2: Negev: land, water, and civilization in a desert environment

(introduction...)

Introduction

Civilization in the Negev

Freshwater utilization

Conclusions

Bibliography

3: The future of freshwater resources in the Arabian peninsula

(introduction...)

Introduction

Water resources

Water requirements

Management options

Conclusions

References

4: Water resources and agricultural environment in arid regions of China

(introduction...)

Introduction

Water resources

Water utilization and agricultural environment

Improving water management for sustainable agricultural development

Conclusions

References

5: The development of groundwater resources on the Miyakojima Islands

(introduction...)

Introduction

Outline of the Miyakojima Islands

Geology and the hydrological cycle

Outline of the irrigation project on Miyakojima

The construction and concept of the underground dam

The Construction of the Cut-off Walls

The construction of the intake facilities

The storage situation of the Sunagawa underground dam

Conclusion

Bibliography

6: Global warming and groundwater resources in arid lands

(introduction...)

Quaternary climate history

Global warming and desertification

Characteristics of groundwater in arid lands

Utilization and conservation of groundwater

Conclusions

References

7: Sustainable development of freshwater resources in arid lands: Panel discussion

8: Closing remarks

(introduction...)

References

Contributors

Other titles of interest

Conclusions

1. A history of the climate indicates that the present interglacial period corresponds to a desertification period in arid lands. There is much evidence that the climate of arid lands has been very variable since the last glacial maximum. Climatic changes are different from region to region, as indicated by changes in precipitation in the Dead Sea and the Indus River basin.
2. The SST has increased markedly in the low latitude ocean during the past 60 years. The global energy and water cycle has intensified in response to the increase in SST, resulting in an increase in precipitation in some regions and a decrease in other regions. Generally speaking, the precipitation in arid lands seems to be on a decreasing trend.
3. The residence time of groundwater in arid lands is very long, which suggests a relatively small amount of natural recharge compared with the huge amount of groundwater reserve. High salinity in groundwater is a result of long residence time in the aquifer but, in arid lands, shallow groundwater with shorter residence time is also highly saline in some cases.
4. Basic scientific research is needed for the proper management of soil and water in arid lands. Recently, interesting results about the role of surface dry layer that reduces evaporation loss from the soil surface have been obtained.