By Gabriel Andre – Art in Tanzania internship
Environmental Advocacy Program
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 depend on the agricultural sector (80% of the population), which is highly sensitive to climate change, Tanzania is considered particularly vulnerable to climate change. Climate change impacts are already taking a significant toll on the livelihoods and wellbeing of Tanzanians, including:
The rising of severe droughts frequency and its associated water scarcity issues, slow down in the food production chain, economics and poverty reduction 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 water into aquifers (diagram) in low-lying coastal areas and, on a more global scale, the impacts of coastal flooding. Climate projections for Tanzania include increased periods of prolonged drought, more erratic rainfall patterns (leading to extreme flooding) and rising 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, it will likely have a profoundly negative impact on public health, stifling future development in both urban and rural settings.
2. Projections from today to 2100
In this section, I will illustrate the transformations we can expect in various sectors in Tanzania, including energy, agriculture, water, and health.
Before going into technical information, it’s essential 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 Pathway (RCP) is a scenario of greenhouse gas concentrations.
(Not emission) trajectory adopted by the Intergovernmental Panel on Climate Change (IPCC). They described different climate futures depending on the volume of GHGs emitted in the years to come. Founded by the World Meteorological Organisation (WMO) and the United Nations Environment Programme (UNEP), the IPCC’s role is to provide objective scientific information to understand the risks of human-induced climate change and draft recommendations for action.
The IPCC has envisioned various scenarios, including 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’s climate change future, we will focus only on RCP 2.6 and RCP 8.5.
RCP 2.6 requires that CO2 levels will start decreasing by 2020 and reach zero by 2100. Methane emissions (CH4) are at half the 2020 level, and sulphur dioxide has declined to approximately 10% of the levels in 1980-1990. In simple terms, we will be able to respect the Paris Agreement and likely keep global temperature rise under 2 °C by 2100. We will have to face new environmental conditions that are still close to the actual ones, but our daily lives 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 a fertility collapse will occur globally, without considering Africa. For example, Nigeria’s population is expected to rise from 175 million currently 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 living 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 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 the form of water vapour, 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 10 years is projected to increase, which can lead to flooding.
Nowadays, Tanzania is affected by seasonal temperature and climate variations. The 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?
RCP 2.6
Compared to historical data, between 2080 and 2099, Tanzania is expected to experience a variation of around 75mm in its maximum precipitation (January and November), which is likely to exacerbate floods in coastal regions and the Victoria Lake region. In other words, the rainfall season will become more intense each year, but Tanzania will have time to adapt to these new conditions. Innovations will engender better management in the agricultural and energy sectors. On the left are monthly precipitation projections for 2020-2039. On the right are monthly precipitation projections for 2080-2099. In the case of the RCP 2.6 scenario, the difference in 50-80 years is not considerable.
RCP 8.5
In the case of RCP 8.5, monthly precipitation is expected to increase drastically, resulting in a maximum precipitation level difference of approximately 150 mm in January. On the left are the monthly precipitation projections for 2020-2039. On the right are monthly precipitation projections for 2080-2099 in the RCP 8.5 scenario.
In both cases, precipitation concentration will increase, intensifying future floods, albeit not to the same extent. Indeed, in the diagram above, the RCP 8.5 scenario illustrates the impact of the “business as usual” approach on the 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 primarily affected. For example, the transportation lines for fuel could be interrupted by local floods for days or weeks, or the network distribution could be disturbed by excessive rainfall and flooding. Agriculture will be severely impacted, with farm crops often swept away by floods, which will drive Tanzania deeper into poverty.
Drought: extreme events
Both power demand and production are tied to water availability. This is most directly the case in hydropower systems. However, dry conditions may also accompany higher temperatures, thereby heightening cooling needs and increasing demand for water pumping, particularly in regions with intense agriculture.
On the production side, water is required to cool the power plants. If there is insufficient water, cooling is restricted, and production might need to be slowed. In some places, regulations prevent power plants from increasing the temperature of returned water above specific thresholds, which can be hazardous to local fish and plants. These thresholds are faster if stream flows are low during dry conditions. In a few regions, excessive moisture can also be an issue, as water may need to be removed.
RCP 2.6
Concerning agriculture, drought can disrupt demand and production because exposure of soils to high temperatures and scarcity of water can result in soil infertility.
In the RCP 2.6 scenario, the temperature is projected to rise to 2.5 degrees, with extreme variations. Usually, 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.
RCP 8.5
In the RCP 8.5 scenario, temperature will rise from 3 degrees to maximum 6 degrees! It will drastically change Tanzanian’s habits in terms of energy supply. Disruption of operations and distribution will become a significant problem due to the rising demand of a 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 considerable 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 Tanzanian society must take a responsible approach to its environment by focusing on green energy sources and avoiding fossil fuels.
In the case of the RCP 8.5 scenario, environmental conditions are expected to increase drastically, leaving insufficient time for farmers and energy companies to adapt their methods. Those changes will submerge both sectors. Agriculture will face prolonged drought periods, rendering soils incapable of growing crops, and then follow long-term rainfall, causing incessant flooding. Here, too, the farmers will not have time for transition, and the crops will be drowned 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 during flood periods will be complex due to poor road conditions.
Þ Water sector: Lake Victoria case
Africa’s Lake Victoria is the largest tropical lake and the source of the Nile River. Climate changes will affect Lake Victoria’s evaporation, temperature, rainfall, and solar energy. According to Emily Beverly, assistant professor of sedimentary geology at Baylor University, Lake Victoria “could have no outlet to the White Nile in at least ten years”. This means that every significant port will be landlocked, and Kenya could lose access to the lake for a maximum of 400 years. More than 40 million people live in the Lake Victoria basin, and this result will significantly impact their economy. Tanzania relies on the lake’s freshwater, which provides approximately 1 million tons of fish annually. Tanzania’s fishing industry is expected to decrease significantly, and this shortage will have a direct impact on all northern regions.
Even with increased precipitation 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 refill.
The diagram illustrates the drought’s impact on Victoria Lake, where more than half of the Tanzanian lake area is expected to be affected.
Moreover, the demand for drinkable water is also expected to rise with the increase in temperature.
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 surrounding Kilimanjaro (Hai, Moshi rural, Moshi urban, Mwanga, Rombo, Same), which are entirely dependent on them, representing more than 3 million people.
Finally, rising sea levels will constrain most 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 in rural areas, most of them will not be able to feed themselves, and starvation will become increasingly familiar over the years. Due to this malnutrition, many individuals will be more susceptible to contracting communicable or non-communicable diseases. According to the World Bank data, 54% of causes of death in Tanzania were caused by infectious diseases and maternal, prenatal and nutrition conditions.
Malaria is still also a significant issue in Tanzania. In 2018, the incidence of Malaria was 124 per 1000, which represents 7.4 million people at risk. The rise in tropical temperatures and floods will increase the mosquito population, and therefore, the risks of contracting yellow fever, malaria, Zika virus, chikungunya, and many other diseases.
Finally, according to the RCP 8.5 scenario, poverty will increase, and consequently, the population will not be able to face massive floods. With 49% of the population living on less than $1.90 per day, with houses on the ground and only a sheet of metal as a roof, we can easily imagine the catastrophe.
In conclusion, if Tanzania adopts the pathway of green energy, which means avoiding coal and oil, the two primary fossil fuels used, and if the government implements a massive environmental sensitisation campaign, Tanzania could likely face the RCP 2.6 scenario. As always, the public and private sectors are the biggest drivers of gas emissions; otherwise, the country will face, in the worst case, the RCP 8.5 scenario. As seen before, these scenarios would be a disaster for a developing country like Tanzania, which faces extreme events and unbearable conditions.
