By Gabriel Andre – Art in Tanzania internship
THE IMPACT OF CLIMATE CHANGE IN TANZANIA
1. What can be expected
Tanzania is a coastal country in East Africa which shares the Victoria Lake border with Kenya and Uganda. Given that the vast majority of the population’s livelihoods are dependent on the agriculture sector (80 % of the population) which is highly sensitive to climate change, Tanzania is considered to be particularly vulnerable to climate change. Climate change impacts are already taking a significant toll on the livelihoods and wellbeing of Tanzanians, including:
Rising of severe droughts frequency and its associated water scarcity issues, slow down in the food production chain, economics and poverty reductions gains, reduced quantity and quality of the water in Victoria Lake, including an increase in contaminants which impact the purity of the water and have the potential to harm health, reduced surface water flows and aquifer (see diagrams below) that recharge during drought periods, as well as groundwater depletion through aquifer over extraction.
Furthermore, we can anticipate the intrusion of saline into aquifers (diagram) in low-lying coastal areas, as well as on a more global scale, impacts from coastal flooding. Climate projections for Tanzania include increased periods of prolonged drought, more erratic rainfall patterns (leading to extreme flooding) and a rise of sea-levels, all of which may exacerbate the mentioned pressures on water resources in this already water stressed country. If Tanzania’s low capacity for climate resilience is not addressed, this will likely have a profound impact on public health, stifling future development in urban and rural settings alike.
2. Projections from today to 2100
In this section, I’m going to illustrate what transformation we can expect in different sectors in Tanzania such as energy, agriculture, water, and health.
Before going into technical information, it’s important to understand how those sectors will be impacted. In most of the diagrams, there will be two baselines: RCP 2.6 and RCP 8.5
The Representative Concentration Pathways (RCP) is a greenhouse gas concentration
(Not emission) trajectory adopted by the Intergovernmental Panel on Climate change (IPCC). They described different climate futures depending on the volume of GHG’s emitted in the years to come. Founded by the World Meteorological Organization (WMO) and the United Nations Environmental program (UNEP), IPCC’s role is to provide objective with scientific information to understand the risk of human induced climate change and drafted recommendations to act in consequence.
IPCC has foreseen many different scenarios such as RCP 1.9, RCP 2.6, RCP 3.4, RCP 4.5, RCP 6, RCP 7 and RCP 8.5. In the following analysis of Tanzania climate change future, we are going to focus only on RCP 2.6 and RCP 8.5.
RCP 2.6 requires that CO2 will start decreasing by 2020 and go to zero by 2100. Methane emissions (CH4) are going half the CH4 level of 2020 and Sulphur dioxide declined to approximately 10% of those of 1980-1990. In simple words we will be able to respect Paris Agreement and likely to keep global temperature warming rise under the 2*C by 2100. We will have to face new environmental conditions, that are still close to the actuals one’s, but our daily life will remain comfortable.
RCP 8.5 as you can imagine is another story. It’s the worst climate change scenario with a very high baseline emissions scenario. Experts see it as the “business as usual” scenario.
RCP 8.5 scenario assumes that by 2100 there will be between 9.6 billion and 12.3 billion people. Assuming that the collapse of fertility will occur in the entire world without considering Africa. For example, Nigeria’s population will rise from 175 million nowadays to 1.5 billion by 2100. Almost all the fossil energies will be consumed, and we can expect that southern Europe will be the new Sahara. Most of the people on the planet will be leaving in extreme conditions. A scenario where giving birth in 2100 would be condemning your children to a hopeless life.
Let’s then focus on the impact of those scenarios on Tanzania through those sectors. Most of the following diagrams in this section are being taken from the Climate Change Knowledge Portal of the World Bank group. https://climateknowledgeportal.worldbank.org/country/tanzania-unitedrepublic/climate-data-projections
Þ Agriculture and Energy sector
Precipitation: extreme events
As warmer air has a higher capacity to carry moisture in form of water vapor, future climate raises the likelihood of strong rainfall events, towards the extremes. In many
places around the world, the maximum expected amount of rainfall in a 10-year period is projected to increase, which can lead to flooding.
Nowadays, Tanzania is issued to this seasonal temperature and climate variation. Rainfall period starts in December and ends at the beginning of April. Then, the easter season arrives with comfortable temperatures, consequently causing the arrival of millions of tourists.
What would be the projection of this monthly precipitation in RCP 2.6 and 8.5 scenarios?
Compared to historical data, between 2080-2099, Tanzania will face variation around 75mm maximum (January, November) of its precipitation which will reinforce floods in coastal regions and in the Victoria Lake region. In other terms, the rainfall season will be each year more intense, but Tanzania will have time to adapt to those new conditions. New innovations will engender better management in the agricultural and the energy sectors. On the left, monthly precipitation projections for 2020-2039. On the right, monthly precipitation projections for 2080-2099. In the case of RCP 2.6 scenario, the difference in 50-80 years is not considerable.
In the case of RCP 8.5, monthly precipitation will drastically increase leading to a maximum precipitation level difference of around 150mm in January. On the left monthly precipitation projections for 2020-2039. On the right, monthly precipitation projections for 2080-2099. In the RCP 8.5 scenario.
In both cases, precipitation concentration will increase, which will intensify future floods, yet not with the same intensity. Indeed, in the diagram above, RCP 8.5 scenario demonstrates the impact of “business as usual” attitude towards Tanzanian climate. It is clear that if we were to find ourselves in the situation of the diagram on the right, business will not be as usual. Power production will be largely affected. For example, the transportation lines for fuel could be interrupted by local flood for days or even weeks, or the networks distribution could be disturbed by excessive rainfall and flooding. Agriculture will be hit critically with farm crops always swept by floods which will drive Tanzania into a deeper poverty.
Drought: extreme events
Both power demand and production are tied to water availability. Obviously, this is most directly the case in hydropower systems. Although, dry conditions might also come along with higher temperatures, thus heightened cooling needs and an increase in demand for water pumping, particularly in regions of intense agriculture.
On the production side, water is required for cooling the power plants. If there is not enough water, then cooling is restricted, thus production might need to be slowed down. In some places, there are regulations preventing power plants from causing an increase in the temperature of returned water above specific thresholds, which are dangerous for local fish and plants. These thresholds are more quickly reached if stream flows are low during dry conditions. In a few regions, too much moisture can also be an issue as water might need to be removed.
Concerning agriculture, drought can disrupt its demand and production because the exposition of soils to high temperatures and the scarcity of water can result in the infertility of soil.
In the RCP 2.6 scenario, temperature will rise for 2.5 degrees with extreme variation. Normally it will stay around the 1 degree rising prediction. The temperature will still promote comfortable living. Both energy and agricultural sectors will remain possible thanks to technical innovation.
In the RCP 8.5 scenario, temperature will rise from 3 degrees to maximum 6 degrees! It will drastically change Tanzanians habits in terms of energy supply. Disruption of operation and distribution will become a major problem because of the rising demand of growing population and evolving power needs. In the same case, demand for agriculture will rise but production will decrease because of soil infertility. With 80% of the population living on agriculture, feeding Tanzania’s population will be a huge challenge. Moreover, the breeding of goats and cows will face a lack of grasslands and associated difficulties sustaining livestock.
To sum up, in the case of the RCP 2.6 scenario, environmental conditions will increase progressively, leaving time to find innovations and new management methods to keep demand and production at a sustainable level. That also means, that the Tanzanian society will have to take a responsible pathway for its environment by focusing on green energies and avoiding fossils energies.
In the case of the RCP 8.5 scenario, environmental conditions will increase drastically without leaving time for the farmers and energy companies to adapt their methods. Both sectors will be submerged by those changes. Agriculture will face long drought periods making soils incapable of growing any crops, and then will follow long term rainfall causing incessant floods where here also, the farmers will not have the time for transition and crops will be drown and washed away. Electricity will face high demand for cooling, hence conditions for living workers in both extreme periods will be inhumane. Finally, supply, production and distribution in flood periods will be difficult because of poor road conditions.
Þ Water sector: Lake Victoria case
Africa’s Victoria Lake is the largest tropical lake and source of the Nile River. Climate changes will affect Lake Victoria’s levels of evaporation, temperature, rainfall, and solar energy. According to Emily Beverly, assistant professor of sedimentary geology at Baylor University, the Lake Victoria “could have no outlet to the White Nile in at least ten years”. Which means that every major port will be land closed and Kenya could lose access to the lake in a maximum of 400 years. More than 40 million people are living on the Lake Victoria basin and this result will badly affect their economy. Tanzania depends on the lake’s freshwater because it provides 1 million tons of fish annually. Tanzania’s fishing industry will decrease highly, and all northern regions would be directly affected by this shortage.
Even with an increase of the precipitations in Tanzania (monthly precipitation diagram 2080-2099), in the RCP 8.5 scenario, temperatures will be so high that the lake will dry out too quickly for it to fill up.
The diagram shows the drought impact in the Victoria Lake where more than half of the Tanzanian lake area will be affected.
Moreover, with the rise of temperature, the demand for drinkable water will equally rise.
Global warming will cause the ice on Kilimanjaro and Mount Meru to melt irreversibly.
Neither of these sources will be able to provide drinking water to the districts around
Mount Meru (Arumeru, Arusha, Karatu, Monduli, Ngorongoro) and those around the Kilimanjaro (Hai, Moshi rural, Moshi urban, Mwanga, Rombo, Same) who are completely dependent on them, representing more than 3 million people.
Finally, the rise of sea levels will constrain a majority of Zanzibar’s population to immigrate to the mainland.
Þ Health sector
Most economic sectors will be affected by climate change (agriculture, energy, fishing, etc.) and the impact on those sectors will result in many adverse effects on the human health of the Tanzanian population. With 80% of the population living on local agriculture, most of them won’t be able to feed themself and starvation will be become through years, common. Because of this malnutrition, many will be inclined to face communicable or non-communicable diseases. According to the World Bank data, 54% cause of death in Tanzania were by communicable diseases, maternal, prenatal and nutrition conditions.
Malaria is still also a major issue in Tanzania. In 2018, the incidence of Malaria was 124 per 1000 which represents 7.4 million people at risk. The rise of tropical temperature and floods will increase the mosquito’s population and therefore the risks of obtaining yellow fever, malaria, Zika virus, chikungunya and many others.
Finally, according to the RCP 8.5 scenario, poverty will increase consequently, and the population won’t be able to face massive floods. 49% of the population living under the 1.90$ per day, with houses on the ground and only a sheet of metal as roof, we can easily imagine the catastrophe.
In conclusion, if Tanzania takes the pathway of green energy which means avoiding both coal and oil, the two major used fossils energies, and if a massive environmental sensibilization campaign is implemented by the government, then Tanzania could likely be faces the RCP 2.6 scenario. As always, the biggest drivers of gas emissions are the public and private sector and there are the ones who have to give the example. Otherwise, the country will face, in the worst-case, the RCP 8.5 scenario. As seen before, these scenarios will be a disaster for a country in development such as Tanzania which faces extreme events and unbearable conditions of life.