Intense Rainfall Caused by Climate Change

This blog aims to assess the impacts of intense rainfall on water resources.  According to the Clausius-Clapeyron relation, as temperatures increase the moisture holding capacity of the atmosphere will also increase (Owor et al 2009).  This relationship is exponential, hence with an increase of global temperatures by 2^oC, a warmer country such as Tanzania in Sub-Saharan Africa may be effected to a greater degree, compared to a cooler country such as the UK (Figure 1).  In Sub-Saharan Africa it is expected, that precipitation will occur less frequently but more intense, due to the holding capacity of moisture increasing by 6.5%K^-1 (Taylor et al 2012). 

Figure 1: Clausius-Clapeyron Relation, trends of temperature versus vapour pressure

Implications of intense rainfall

The El Nino Southern Oscilation event (ENSO), occurs once or twice per decade, this is an extreme event with intense rainfall. During ENSO events in Makutapora, Tanzania, intense rainfall is advantageous for the country, as most groundwater recharge occurs during this event (Figure 2).  Semi-arid and arid regions are heavily dependent on groundwater as a freshwater resource, hence an increase in intense rainfall due to climate change may be advantageous in Tanzania, creating more available water for domestic and agricultural use (Taylor et al 2012). Additionally, the increase in groundwater levels, may help reduce drought effects that may occur during dry periods.

Figure 2: Rainfall versus Groundwater Recharge in Tanzania Source: Taylor et al 2012

Conversely, intense rainfall can be a disastrous event as seen in West Africa (e.g. Niger, Sudan, Sahel). In many cases, floods may occur, and crops are likely to wilt as they take vast amounts of water in a short period of time.  This could lead to a large decrease in crop availability, leading to food shortages.  During 2007, in Senegal, food shortages, lead to famine, economic decline and some riots (Tschakert et al 2010).  Additionally, floods create stagnant water, resulting to diseases such as cholera and malaria.  Hence, the livelihood of people may deplete.

Thoughts:

It is suggested that intense rainfall may increase groundwater recharge, thus replenishing the area.  Conversely heavy rainfall can lead to catastrophic events, where food decreases and economies may be severely affected.  Therefore it is essential, to predict the negative impacts of intense rainfall for specific areas and try to prepare in advance.

 Can’t wait to hear your thoughts!

Water and Environmental Change: An Introduction

Welcome to my blog!  My blog will be focused on how various environmental changes, will affect water availability in Sub-Saharan Africa and how this may impact people and food sources.  This investigation will take place through various academic articles, news articles, books and videos that I may find interesting.  Please, feel free to add your own contributions to these discussions. 

Why am I interested in water and environmental change?

Freshwater resources are only around 5% of the world’s water resources and are found in the form of surface water (i.e. rivers, lakes), groundwater and glaciers (Price 1996).  Climate change is causing global increases in temperatures on Earth.  It is accepted by many researchers the average temperatures of Earth will increase by a minimum of 2^oC, hence leading to high evapotranspiration rates (IPCC 2014).  As temperatures increase, according to the Clausius-Clapeyron relation, the holding capacity of moisture in the atmosphere will increase, leading to less frequent but more intense rainfall events (Owor et al2009).   Additionally, extreme events such as droughts are expected to become more recurrent due to the climate change impacts (IPCC 2012).  Hence, the hydrological cycle will be negatively affected, leading to water availability and quality deterioration. 

 

Droughts in Sub-Saharan Africa (imagine this occurring more frequently)
Source: Photojournalism 

Consequently, we expect that people will also be negatively impacted.  It is likely that their livelihood will deteriorate, as domestic water availability may be less accessible.  Water for agriculture and industry may not be as largely available as in the future.  Hence, a domino effect may occur and the countries’ economies may be negatively affected as agricultural supply may deteriorate drastically affecting international markets.

Why Sub-Saharan Africa?

Most countries in Sub-Saharan Africa are developing countries.  Water availability is still of great concern, as in many cases water is not found in households.  Instead it is found at communal taps, springs, wells or even from vendors (Thompson et al 2000).  Due to this difficulty in water access, it is a great concern on how water availability and sustainability may be in the future in Sub-Saharan Africa, when considering the climate change impacts.

Concerns:

This blog aims to discuss these concerns:

• How will freshwater be affected with increasing climate change impacts?
• How will water levels and availability affect people?
• How will water levels and availability affect agriculture, industries and economies?

Join me on a trip to investigate these concerns.