Merry Christmas (Eve)

So, this is my final blog post for this module. This has probably been one of the most challenging university projects, in being consistent at producing weekly blog posts for two different modules. However, it has been one of the most interesting and engaging projects I have completed to date.

Throughout this blog I have examined the hydrological impacts that have already and will occur in East Africa due to climate change. I have also reviewed this in the context on land use change. What is important to note is that climate change is not a future phenomenon, it has been occurring for many decades.  What has been particularly interesting is that East Africa is an extremely diverse region, with different areas experiencing varying hydrological impacts. Therefore, there is a fundamental need to focus on regional and local aspects of climate change.

Climate change is not only changing the frequency of extreme weather events, but also seasonality, intensity and duration. During the coming century, increasing population, changing pattern of water use, and concentration of population and economic activities will pressurise Africa's water supply. Therefore, adaptive and mitigation strategies, both institutional and local are needed to be employed to reduce vulnerabilities, and allow this continent to flourish and develop more proportionally.

Source: http://www.greenpeace.org/africa/en/campaigns/Ecological-Farming-in-Africa/ClimateResilience/

Remember in a warming world, not all Africa's taps will run dry.

Rift Valley Fever

What is Rift Valley Fever?

Rift Valley Fever (RVF) is a virus transmitted by mosquitoes and blood feeding flies that usually affects animals but also affects humans. The virus was first identified in 1931 during an epidemic among sheep. Since then outbreaks have been reported in SSA, North Africa, and in 2000 Saudi Arabia and Yemen.

The occurrence of RVF is known to follow periods of widespread and heavy rainfall associated with the development of strong ITCZ. Heavy rainfall floods mosquito breeding habitats, known as "dambos" in East Africa, providing an ideal environment for naturally infected mosquito eggs to hatch (Figure 1)/

Figure 1: Rift Valley Fever Ecology

Source: https://www.climate.gov/news-features/understanding-climate/el-niño-east-africa-and-rift-valley-fever

In 2006-2007, outbreaks in Kenya, Somalia, Tanzania, Sudan, and Madagascar caused > 200,000 human infections and led to roughly 500 deaths. In Kenya alone, the outbreak cost $32 million in livestock losses and international export bans. An outbreak in 1997 caused 170 haemorrhagic fever associated deaths and ~27,500 infections. The most serious outbreak on record occurred in Kenya 1950-51, and resulted in the death ~100,000 sheep (Greenhalgh, 2015).

Predicting outbreaks

Enso is recognised to be linked with outbreaks of RVF in East Africa. 2015 stood out to be one of the top three El Nino events since 1950, Sudan, Ethiopia, Somalia, Kenya and Tanzania were identified as areas at risk for RVF due to substantially elevated rainfall (figure 2)

Figure 2: 2015 projections of extreme rainfall and RVF outbreaks

Source:https://www.climate.gov/news-features/understanding-climate/el-niño-east-africa-and-rift-valley-fever

Climate Change

More extreme rainfall events are projected in East Africa with warmer temperatures. These events will create the necessary conditions for more RVF outbreaks not only in East Africa, but also potential for it to expand its geographical range (Martin, 2008). 

Future projections

A study 'Environmental Change and Rift Valley fever in eastern Africa: Projecting Beyond Healthy Futures', focussed on the Republics of Burundi, Kenya, Rwanda, Uganda and Tanzania. The two pathway scenarios RCP4.5 and RCP8.5, indicate increased temperatures, rainfall and variability. Results highlight high- risk of future RVF outbreaks, including parts of East Africa that are currently unaffected. The results also highlight the risk of spread from/ to the study area, and possibly further afield. The greatest projected changes in RVF outbreaks are in Kenya and Tanzania. Changes remain stable up to 2050, when compared with baseline results, even declining in central/ eastern Uganda (RCP4.5), before increasing by the end of the century. Positive changes are most evident to the West of Lake Victoria (Berundi, Rwanda and Western Uganda) and in Western Kenya, especially under RCP8.5 by the end of the century.

The study also combined results of a spatial assessment of social vulnerability to the disease in Eastern Africa. Predisposition to RVF is greatest where the boarder of North-eastern Uganda, North-western Kenya and South Sudan meet, because of the co-occurrence of highly seasonal rainfall, relatively high densities of livestock, high levels of poverty and poor infrastructure, including health services. Under RCP4.5 risk decreases in Southern and Central Uganda, however increases in Central Kenya. For RCP8.5 risk patterns are similar however, RVF has expanded again in central and Southern Uganda, and is greater in Western Kenya.

Results show that with increasing extreme precipitation events, there is a clear need to remain vigilant and to invest not only in early warning systems, but also in addressing the socio-economic factors that underpin social vulnerability in order to effectively mitigate future impacts (Taylor, 2016).

Land use change as important as climate change

Throughout this blog, I have vaguely touched upon land use change. However, this too, is an important factor affecting the hydrological system in East Africa.

As shown in previous posts, agriculture largely contributes to the East African economy. Although a very risky enterprise due to increasing rainfall variability, many East African farmers have adapted to their variable climate in very successful ways- this is often results in the modification of land- cover and/ or land- use type. These effects have shown to have significant impacts on rainfall, as well as GHG effects (Moore, 2015).

Land- use change and drivers

Some of the main land use conversions in East Africa can be summarised as:

1. An expansion of cropping into grazing areas, esp. in semi- arid to sub- human areas
2. An expansion of rainfed and irrigated agriculture in wetlands or along streams esp. in semi- arid areas
3. A reduction in size of many woodlands and forests on land that is not protected
4. An intensification of land use in areas already under crops in the more humid areas
5. the maintenance of natural vegetation in most protected areas

What are the drivers of land use change in East Africa?

1. Government policy, laws and regulations 
2. Economic factors
3. Population growth and migration
4. changes in land tenure arrangements
5. Access to markers
6. Environmental conditions

Land use and climate change 

In a study 'projected land- cover change effects on East African Rainfall under climate change', Moore (2015), examines the regional responses to GHGs, Landcover/ land use change (LCLUC), and their combined effects in East Africa. The aim was to further understand how hydrological mechanisms might be altered by LCLUC in future scenarios. The four different scenarios they used were:

1. Current land- cover and current climate
2. current land- cover and future climate
3. Future land- cover and current climate 
4. Future land-cover and future climate

It found that LCLUC can affect precipitation in several ways:

• Increase in albedo from the change in land cover from forest to crop lands, can result in surface cooling, which can reduce convective rainfall.
• An increase in the amount of suspended dust from overgrazing which removes large amounts of vegetation. This can result in radiative cooling, and therefore a decline in (convective) precipitation.
• Intensive rainfall is also caused by LCLUC due to an increase in intensive convection. These convection changes can enhance the local sea breeze effect. As shown previously, East Africa is already and will face more extreme weather events due to increased GHGs. LCLUC has the potential to increase the risk to floods and damage to agriculture in coastal areas where forest has been replaced with agriculture.

Results show that GHG and LCLUC may slightly differ in how they alter regional precipitation patterns. One of the most important findings is that projected precipitation changes around major populated areas may be as strongly influenced by LCLUC and as by GHG effects. Precipitation in areas which have a large population density were more influenced by LCLUC than GHG, due to higher human and agricultural systems. GHG effects on precipitation, largely has wide scale implications, whereas LCLUC have more regional and local impacts.

This paper has shown that Climate change and land use change are not two separate forces affecting the distribution of precipitation; instead they are interrelated. Figure 1 clearly depicts this.

Figure 1: framework of land use/ cover linkages and flow dynamics among driving forces, bio-physical system, and climate change

Source:http://www-tandfonline-com.libproxy.ucl.ac.uk/doi/pdf/10.1080/19376812.2014.912140?needAccess=true 

Impacts on river basins

What are the impacts on river basins? A study on the Mara River Basin, Kenya found that any further conversion of forests to agriculture and grassland in the basin headwaters is likely to reduce dry season flows and increase peak flows, leading to greater water scarcity at critical times of the year and exacerbating erosion on hillslopes.

     
      Most projections call for precipitation increase of 5-10% in this century. This can suggest greater future availability of water resources in this basin. However, results from this study conclude that together with increases in evapotranspiration (from warmer temperatures) and potential increases in aquifer recharge, runoff will be limited. Water balance showed non- linear responses to climate change. Small decreases precipitation may produce large reduction in runoff because of reduced runoff and increased evaporation.

Therefore, model results support protecting headwater forests and indicate that additional emphasis should be placed on improving land management practices that enhance infiltration and aquifer recharge as a part of a wider program of climate change adaptation.

Concluding thoughts

This post has shown that land use change does have a large influences over change in precipitation. Although, these may be localised in comparison to climate change, they should be incorporated into rainfall projections, as well as mitigation and adaptation strategies. 

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COP22

World Climate Simulation

Last week as part of my Global Environmental change module, we took part in the world climate simulation. As part of this, we had to act as a negotiator at the united Nations Climate Change negotiations. I was part of a team of 4 acting as delegates from the united States. In the 3 hours, teams from each region had to negotiate to try and get temperatures down to 1.5℃. We managed 2.1℃. It showed how challenging it can be to reach agreement between different regions, how complicated politics can be and how tensions can rise very quickly. 

The exercise is framed by current climate change science, using the interactive C-ROADS computer simulation which allows participants to find out how their proposed policies impact the global climate system in real- time. We went into this not really knowing how COP (Conference of the parties of the United nations agreement on climate change) worked, and we left with so much more knowledge and understanding.

I would definitely encourage students (not only geography), schools, lecturers, businesses, leaders, everyone to get involved. Below is a video of how this climate simulation works:

Mock video of how the world climate simulation works

But what does this have to do with Water and Environmental change in Africa?

COP22 was held in Marrakesh 7-18th November 2016. For the first time in history, a water action day was the highlight of the third day. World Water Action day aimed to highlight the water sector as a provider of solutions for implementing the Paris Agreement (COP21). 

Countries have identified water as key to adaptation in 93% of their national climate action plans. Water is the key to food security, human health, energy production, industrial productivity, biodiversity, as well as a basic human need. Therefore, ensuring water security means ensuring security in all these domains.

From the Water Action Day, "Water for Africa" was officially launched. This initiative aims to mobilise different international political, financial and institutional partners to develop an emergency action plan to confront climate change and improve water and sanitation services and management in Africa.

Concluding thoughts

Water needs to be seen as an end in itself, rather than merely a means to an end.

The importance of water seems to be highlighted through its critical role in other domains. It is a start that the sheer importance of water is now being acknowledged on the platform of COP, through the action day. However, I believe more needs to be done, to bring to the attention, that climate change is drastically changing the distributions of water, and this has already and will have many negative implications for many. Long droughts and extreme rainfall, are becoming common for many, so how can this is increasingly unreliable resource be the solution for all the problems arising from Climate Change? 

Africa is the most vulnerable to climate change. Therefore, effective funding and management is necessary, to adapt to the threat of climate change. The $100bn per year promised to be pledged by the developed countries by 2020 in Copenhagen 2009, could be key to this. Although by the end of COP22, there is said be 'extreme disappointment' in the lack of progress in agreement to the distribution of the funding, which has been pushed back to 2018.

Adaptation is key to the survival and development of Africa. A roadmap drawn up by developed countries and presented at Marrakesh allocated just 20% of climate finance, to efforts limiting the damage caused by climate change. The remaining 80% of this money would be spent on mitigation (cutting greenhouse gas emissions). However, I believe that this is an unfair distribution, as the need for adaptation is particularly important in developing countries, which are hit hardest by climate hazards such as droughts and floods.

Throughout this blog I have illustrated through East Africa that water supply is changing and is becoming extremely unreliable. However, this is not the only issue, demand is also changing, it is increasing. One effect of this is changes in land-use. Therefore, next week's post will focus on land use change, and how this, in conjunction with climate change, is affecting Water in Africa.