Climate Change And Water II

Climate change is caused by the rise of global atmospheric temperatures which plays havoc on the entire planetary climate system. This rise in temperatures is occasioned by greenhouse gases which act in the atmosphere by absorbing solar radiation reflected by the Earth.

Now, the essence of climate change is that it is all about one element: water. Climate change interferes with the hydrological cycle, which is the main force of climate. This is why all the effects of climate change: droughts, erratic weather, floods, severe rains, heat waves, stronger storms, sea level rise have to do with water.

It is about water.

photo by aimee\iwaria

As the quantities of greenhouse gases in the atmosphere increase, so does the air temperatures. The ability of air to absorb moisture is increased by temperature, because as the air expands so does its capacity. So as it gets hotter, the more moisture is absorbed from the ground into the air. This higher temperatures rapidly increase the evaporation and transpiration part of the hydrological cycle, thus drying out the land. This is what causes severe droughts.

Dried out land and hotter air results to heat waves.

Heat waves also increase the incidence of wildfires. Drier land is easy to catch fire and this fire spreads out farther and for longer distances than it would in normal circumstances. Lack of rain spurs on wildfires because wet vegetation and water bodies would ideally block the spread of fire.

Then, as more moisture is absorbed in the atmosphere at a higher scale, it eventually distills as severely heavy rain over the surface of the Earth causing flash floods and widespread destruction.

Additionally, as it gets hotter in the atmosphere, the ocean which is the major regulator of climate also gets warmer. In particular, the surface of the sea water gets hotter, and this is one of the precursors of stronger cyclones arising from the ocean. Such storms, like cyclones Ana and Eloise which made landfall in Mozambique cause massive destruction in the human and natural world.

Sea level rise is caused by the melting of polar ice caps and the expansion of water already in the ocean. Heat makes substances expand while cold makes them contract. Hot water has more volume than cold water. This is in addition to the water being added to the ocean because of sea ice and glacier melt.

So the warmer it gets in the atmosphere, the more the level of water in the sea will rise and this threatens coastal cities and island nations in particular. It also affects trade and ports.

Now, in the human world, this has several impacts. Drinking water is a normal part of human and animal life, and lack of it causes death at the worst. A lot of drinking water is from groundwater sources, that is, underground rock formations that bear water. Normally, this water is accessed by drilling or when the aquifer naturally meets the surface of the ground. Groundwater is replenished by rainwater. Severely heavy rains fill up the aquifer faster than natural filtration systems beneath the ground can remove pollutants like pesticides. This poses the threat of water contamination.

Furthermore, with erratic weather and longer and more severe droughts, there is less water going underground and this endangers water security. Some places rely on surface water which is also recharged by rainwater and snowmelt. Glacier melt is what feeds rivers and streams during spring and summer, and supplies drinking water.

But this is also reduced by drought. Moreover there’s lesser amounts of snow falling compared to the past.

Shared water resources are water bodies that are shared by multiple countries. An example is the Nile River, or River Congo. Such natural features are important for the wellbeing of different countries because they are part of the economy as well. An example is Egypt, which depends on the Nile for survival, a river which is arises from Lake Victoria and passes through other countries like Uganda, Sudan and Ethiopia before emptying into the Mediterranean Sea. All these countries have competing interests on the river and changes in water levels because of climate change will of course affect them, and lead to tussles and conflict.

Water availability is what supports agriculture whether rainfed or irrigation. So, as rainfall patterns change because of climate change, agriculture and food security will be negatively affected.

All this can have an impact on conflict and security as increasingly scarce water resources face more pressure from people and the natural world. Human wildlife conflict is likely to escalate, and tensions in human society between different groups will multiply as people compete for the little there is.

The effects of climate change on water is a cause of migration and conflict. Climate refugees are going to become more as people move because of uninhabitable land and in search of water. Social dynamics will eventually lead to conflict, upheavals and security problems.

Security installations near the sea will be submerged by rising seas.

All the above is likely to influence geopolitics and political stability.

Water is also part of energy. In its most basic form, water produces electricity from dammed rivers (hydropower). This electricity is what powers the economy. During extended period of drought, less power will be produced and its cost will go up. This affects economic growth, especially sectors that require power like manufacturing.

Water is also used in thermal (coal, oil) power plants to cool the systems. Lesser amounts of water will therefore affect power generation. In addition, water is used in nuclear power plants for the same reason.

Water is also used in the manufacturing industry, particularly for the cement, chemicals and steel industries. Water is used in most industries as a coolant, and thereafter the waste water is treated and released into the environment. Unfortunately a lot of it is released in its raw form, which is a danger to public health and the natural world.

Climate change acting through water will impact public health. Warmer water supports the growth of dangerous species of algae. These bloom in massive quantities in hotter seasons and pose a health risk. This is because the water contains toxins which renders it unfit for drinking or swimming. It can cause dermatological conditions when applied on the skin and health problems when ingested.

In other ways during periods of intense rain, rain water erodes farmlands, and washes off chemicals like fertilizers and pesticides into rivers and lakes which fertilizes them. This catalyzes the massive growth of water plants and algae, a process known as eutrophication.

This green covering on the surface of lakes and rivers interferes with the natural functioning of the water body. It prevents sunlight from reaching the inner depths of the water and so reducing photosynthesis by phytoplankton and affecting the entire food chain reliant on these tiny water microorganisms.

When these algae eventually die, the decomposition process uses up all the oxygen dissolved in the water and so the marine life like fish which is dependent on oxygen die too.

Fisheries are negatively impacted by climate change. Breeding grounds and fish nurseries are located in cool waters, and so warmer waters affect the reproduction patterns and number of fish being hatched. This affects the seafood industry and coastal economies in general.

Additionally, hotter water spur the multiplication of fish diseases, which is a problem for the marine industry.

Floods also imperil freshwater supplies because they mix with raw sewage in water treatment plants and also by the flooding of landfills. This is an immediate health hazard as drinking water supplies are poisoned with heavy metals and can lead to outbreaks of waterborne diseases.

Because of sea level rise, sea water which is saline slowly encroaches on coastlines and invades freshwater aquifers making the water salty to drink. The invading water also reduces the fertility of agricultural land. Desalination (removing salt from water) is a cost intensive method used to make such water drinkable.

Coastal erosion is another effect of climate change that is pegged on water. Higher and stronger sea waves erode the coast and destroy beaches slowly by slowly.

About 1 billion people globally do not have access to safe drinking water, this numbers will rise because of climate change.

Water as an element is an important part of climate mitigation and adaptation.

When it comes to adapting to climate change in the context of water, it is important to look at the water scarce areas first. Rain water harvesting and storage is the first and easiest method of increasing supplies. Water is stored during times of plenty and used in dry times. Another method is construction of dams, water pans and sinking boreholes. This should have the capacity to store as much water as possible, and this can also be used to generate power.

One of the most important things people can do is planting as many forests as possible. Kenya for example is already doing this, and with some success. Forests attract rain and create a microclimate, buffering against global warming. Reducing wastage, recycling and reusing water is also important, as water can be used for multiple purposes. This would reduce scarcity.

Of course the most important measure is to cut greenhouse gas emissions. If we are to have a fighting chance with climate change, it is imperative to start cutting emissions on a large scale in the present.

Some content is republished from climate and water