What are the regional vulnerabilities in the availability of fresh water to support human needs and sustain freshwater biodiversity, and how can these vulnerabilities be mitigated?

Fresh water is multi-user resource subject to multiple threats including over-exploitation and contamination such that both quantity and quality of water is absolutely limiting for humans in many parts of the globe. Freshwater ecosystems support around 10% of global biodiversity (in less than 1% of the Earth’s surface area), and provide valuable ecosystem services upon which humans depend. Growing human water demands are placing increasing pressure on the ability of freshwater ecosystems to meet human needs, and degrading the capacity of fresh waters to sustain biodiversity. There is evidence that freshwater biodiversity is already undergoing pandemic decline, but responses to these declines at regional or larger scales are lacking. Global climate change and burgeoning populations will exacerbate present conflicts between humans and nature as demands for fresh water increase, but the vulnerability of fresh water biodiversity to impacts arising from this conflict will vary regionally. It is imperative that we identify which regions are now – and which will be – most vulnerable with respect to human needs for water and potential biodiversity loss. These data will provide an essential first step to devising adaptation and mitigation measures intended to ensure that human water requirements can be met without loss of biodiversity or irreparable degradation of freshwater ecosystem function.

In terms of livelihood risks and planning challenges, is rainfall variability more significant than climate change?

Rainfall patterns typically vary in a basin. This variability presents major risks to farmers’ livelihoods and challenges to planners to create proper structures for water storage and conveyance. With climate change, the frequency of extreme events is expected to increase and make the impacts of variability more pronounced. It is therefore important to clarify the significance of rainfall variability and suggest approaches to document and deal with the challenges involved.

How will climate change impact groundwater resources?

Groundwater resources are the main source of drinking water throughout the world. The drivers to their future evolution are linked to most of the remaining uncertainties of climate modelling (future rainfall and intensity of it). Describing precisely the reservoirs geometry and the boundary conditions of aquifers is complex and limit our capacity to estimate the renewable water volume available.

How much change in distribution of demography and agricultural crop types will take place in temperate and tropical regions due to climate change considering present rate of consumption of resources? What are those safer regions which will be the most favorite destinations of migrants affected by global warming, vulnerable events and ground water depletion?

The increasing consumption of earth resources like fossil fuel, mining, pumping out ground water etc. is creating disturbances inside earth and in earth’s atmosphere. These disturbances in earth systems will attract vulnerable events like earthquakes, tsunami, cyclones etc. Regions prone to these vulnerable events will be devastated which will force people to migrate to safer places.

On the other hand, due to global warming and melting of ice, regions like Scandinavia and Russia will get more agricultural land and greenery. This will attract migration of people towards northern parts of these countries. Even people from other parts of Europe, Africa and Asia may shift towards these areas in due course of time. Another factor affecting migration will be sinking of islands due to sea level rise.

Depletion of ground water will also be major factor affecting migration to other places within region or in some cases out of the region (if severity increases). In tropical region like south Asia, glaciers are melting; rivers are not having enough water to recharge the ground water. The uncertainty of monsoon rains is increasing. The rain water is not properly trapped to recharge the ground water, most of it goes as run off. Very soon in these regions, conditions will be so that people will be forced to leave agriculture and migrate to some other places. This will also affect the agricultural patterns and population distribution.

I believe that during next decade, we must focus our research to search the answers of these questions in order to prepare future generation ready against natural and man made disasters. One of the steps of action may be to develop multidisciplinary programs and teams of scientists and modelers including social scientists, political scientists, geophysicists, ecologists and atmospheric and agricultural scientists etc.

Can the environmental impacts of inter-basin transfers be adequately predicted and mitigated?

For large parts of the human population water scarcity is a serious problem. Increased hydrological variability as a result of climate change will exacerbate the problem. As a result, the pressure to use water more efficiently and ultimately to find ways of redistributing resources from areas of plenty to areas of stress increases. There are many large inter-basin transfers around the world, notably in Australia, Canada, China, India and the United States, Central Asia. Many more inter-basin transfer schemes are under consideration. Inter-basin transfers are often large and expensive, involving major infrastructure and in some cases significant use of energy for pumping. Transfers will affect existing river flows and water quality and can also have significant impacts on aquatic ecosystems.

Given the escalating severe impacts on the hydrological cycle, how can we effectively respond to the challenge of climate change adaptation?

Water is the primary medium through which climate change will affect livelihoods, shape economies and alter the natural environment. Recent climate research shows that impacts on the hydrological cycle are likely to be more serious than originally thought. For this reason an assessment of how the resource is managed by humans is crucial.

What are the legal and institutional constraints and opportunities for a water transfer project or the alternatives?

Taking water from one basin to another will affect water rights, whether at the local level or if the basin of origin is a transboundary river. There are a number of ways through which an integrated approach based on multi-national agreements and associated institutional arrangements can result in effective and socially acceptable outcomes of water resources development and use.

How should we identify vulnerable potable water supplies and estimate the cost of adapting these supplies to 2050-2100 ecosystem-level climates?

Availabile potable water is required for human survival. Many supplies around the world are already threatened, and climate change is adding to water-stress. Potable water supplies are a major driver for migration in the developing world.

What are the effects on biodiversity by climate change and the mechanisms of biodiversity to capture, store, and preserve rain water?

Several factors are important for life preservation, including humans. One of the critical ones are water and biodiversity. It is very important to know the relationship water-biodiversity, and the climate change impacts on biodiversity so we can develope strategies to preserve both, water and biological species including their processes.

What are the consequences of ground water reduction on agriculture?

I asked this question and I am concerned that population is growing therefor its food demand and more agriculture productivity means somehow losing soil strength and soil water (soil productivity). This may affect climate regionally. How to address such problem in next decade. If human want to survive than we have to address such question in next decade first rather than discussing water cycle and global warming as they are seems to be periodic.