Global Change and its Impact on Water Resources: the Role of UNESCO’s International Hydrological Programme - Siegfried Demuth and Biljana Radojevic page5


PCCP – From potential conflict to cooperation potential


About 47% of the earth’s surface is covered by transboundary basins. Forty percent of the world’s population depends on the water resources of these basins. Global change and socio-political impacts on water resources increase the pressure over this life spending resource leading to competition and potential conflicts among the various users and sectors. Conflicts can arise regarding allocation, infrastructure, quality of the resources, joint management, irrigation and other activities that are water dependent. From Potential Conflict to Cooperation Potential (PCCP) facilitates multi-level and interdisciplinary dialogues in order to foster peace, cooperation and development related to the management of transboundary water resources. The programme aims to answer the following questions:
  • How do we minimize conflicting environmental and human requirements under climate change threats?
  • How do we resolve conflicts in the best way?
  • What is the climate responsiveness of environmental law on water resources?
PCCP joint research and training activities often allow the concerned parties to find opportunities to enhance their knowledge of the shared water resources, while achieving progress on the cooperation, development and adaptation fronts.

Conclusions

Future challenges for the management of impacts of global change include identifying the dominant drivers in the region under consideration, understanding the underlying processes of the hydrological system, filling data gaps, improving regional cooperation in observation networks and developing comprehensive databases, strengthening international cooperation and developing adaptation strategies to better manage the water resources for a sustainable development.
  • Global Change involves more than Climate Change. There are few areas of the world where river basins, aquifers, etc. are not impacted by the many other drivers related to human activity. The relative importance of climate change and human impact will vary according to the parameter considered. There is a need for further research on attribution, in order to establish the relative importance of climate change and other components of global change on particular elements of the hydrological cycle, in order to clarify this issue.
  • A number of UNESCO and co-operator programs (e.g. GRAPHIC, G-WADI, FRIEND, HELP, IFI, ISI, PUB, GLOWA, Climate/Land use-Floods working group, Global Water Systems Project) currently work on aspects of data collection, problem formulation and analysis of hydrologic issues relevant to global change, and could be leveraged to initiate a coordinated approach to assess and predict hydrologic change, locally, regionally, nationally and globally as part of an initiative to adaptively manage hydrologic risk and mitigate the emerging global water crisis.
  • Arid regions are particularly susceptible to change and the G-WADI programme provides a network that focuses on data collection, modelling, and sharing local adaptation information.
  • The FRIEND network extends to over 162 countries and has been active in many of the relevant areas through sharing and analyzing data, exchanging methods and techniques to account for climate change at a regional level, publications, workshops and international conferences, Their strategic plan is generally consistent with many of the needs envisioned for the initiative described here, particularly where it relates to trend identification and attribution; and risk assessment. However, they do not seem to be directly focused on the management of water resources and adaptation to climate change, but a focus is on the analyses of hydro-hazards and the impact of climate change.



  • The HELP and GLOWA interactions however address some of these goals, especially focusing on the impact of climate change on water resources management and taking into account adaptation measures.
  • Understanding of the processes controlling the geochemical evolution of groundwater and to differentiate between the influence of climate change and human impact on groundwater quality are essential attributes of sustainable integrated groundwater quality and land use management also, in formulating effective groundwater protection policy.
  • Direct human influences on groundwater quality are likely to be more important than climate change for the foreseeable future. Primary climatic stress issues have to do with a) recharge zones, especially for shallow aquifers, and b) sea water intrusion in coastal aquifers, related to sea level rise, perhaps in conjunction with other stresses.
  • Low flows and droughts are affected by human demand and competing interests of users, which will be exacerbated by climate change and ensuing changes in groundwater storage.
  • There will be possibly changes in flood frequency and there is a need for flood prediction as a function of changes due to changes in climate (possibly at large scales). Here land use changes also need to be taken into account (possibly at local scales).
  • Direct human activity is generally a stronger change agent on soil erosion and its hydrologic impacts than climate, although better understanding is needed as to how climate and land cover change lead to erosive and erodibility interactions. Increases and decreases in sediment load in rivers driven largely by land use changes, conservation practices, dam construction and sand mining, but with a potential, as yet un-quantified are also drivers of global change and overrule in some regions the impact of climate change.
  • Changes in glacier dynamics and their impact on base flow and river flow are especially crucial in regions where the population’s water supply depends particularly on headwater catchments.
  • Multi-disciplinary, global data sets sufficiently refined and long enough to allow systematic change analysis and its attribution are needed. They may not exist in many places, and alternate ways to predict and assess changes based on classification and typology development may be needed. New monitoring networks that can aid this classification process and constrain predictions and early warning of change may be useful.
  • Data Availability and Sharing is a major issue that needs to be addressed. For all aspects of change prediction, assessment and modelling, it is critical that benchmark hydro-meteorological data sets be made available. Unfortunately, particularly in the developing world hydro-meteorological data sets are sparse, and globally hydro-geological data sets to support serious assessments and prediction of change in groundwater systems are virtually non-existent. Even where such data have been collected, they are rarely shared across ministries or institutions in the same country or across boundaries. While considerable progress was made on climate change assessment and prediction recognizing that one could model the atmosphere and oceans using coarse resolution global data sets, and then use some means of downscaling, hydrologic change investigations related to climate and land use change and water use will need to be scaled up from a high resolution to the coarse resolution to resolve spatial pathways and change impacts in the context of system risk assessment and management. The data bases to support such analyses need to be developed and their economic utility needs to be demonstrated.
  • There is a need for formal risk assessment and scenario analysis procedures to identify the vulnerabilities to change, to predict risk, to assess the significance of the risk relative to the impact and the uncertainties, and to propose and test adaptation strategies. Both climate and other factors need to be considered in assessing sensitivity to change. Such a framework would be useful to constrain and guide global change research directed at operationally mitigating the aspects of the global water crisis induced by a changing/varying climate or by other global or local factors that induce changes in land and water use.