The Trans-African Hydro Meteorological Observatory (TAHMO) seeks to develop a network of weather stations across Africa. It is important to catalog and make all current and historic climate data accessible so that interested people can start their data analysis efforts, to avoid redundancy in TAHMO installations. This to prioritize the coming years of effort. TAHMO is a joint initiative of TU Delft and Oregon State University. Their aim is to design, build and operate no less than 20,000 inexpensive and robust weather stations across Africa.


TAHMO is a Foundation in the Netherlands. The Foundation also has two NGOs, one in Ghana and the other one in Kenya. At the moment there are 26 people active for TAHMO. TAHMO has a few partners and one of the partners is Farmerline. Farmerline will be discussed in their own section.

The idea behind this project is to develop a dense network of hydro-meteorological monitoring stations in sub-Saharan Africa: one every 30 km. This entails the installation, as said before, of 20,000 such stations. By applying innovative sensor technology and ICT, TAHMO stations are both inexpensive and robust. Stations are be placed at schools and integrated in the educational program, adding richness to the curriculum and helping foster a new generation of scientists. Local weather data will be combined with models and satellite observations to obtain insight into the distribution of water and energy stocks and fluxes. [TAHMO, 2015]


Monitoring Africa’s environment is an important challenge if the continent’s resources are to be used in an optimal and sustainable manner. Food production and harvest predictions would profit from improved understanding of water availability over space and time.

Current situation, before TAHMO

The ability to access historical climate data is critical in order to efficiently manage water resources. The limited number of weather stations in Africa is spread out over enormous distances; most are found in northern and southern Africa, leaving huge data gaps in the central part of the continent.

Additionally, those African climate data which are currently available are not arranged in a convenient way for users to access; data sets are often incomplete and restricted to the public. There is often a lack of communication within countries and regions, creating data gaps at multiple levels. Another key challenge for climate monitoring in Africa, for TAHMO, is the availability of historical data; most collected data have been recorded on paper, and not catalogued electronically.

With these data literally sitting forgotten on shelves in offices around the continent, they are at great risk of being lost forever. Accurate climate data are essential for agriculture, weather prediction and climate modelling. With an increase in quantity and quality of climate stations, along with the incorporation of historical data, we can move forward towards the goal of obtaining accurate climate data. [TAHMO, 2015]

Technical analysis

The TU Delft university and Oregon State university developed and built a sustainable weather station. But how is the weather station formed, why is it reliable? In this section the technical aspects are discussed of the TAHMO weather station, to give insight in the product and the background of the product.

How does it work?

The local weather stations are primarily located at schools and universities connected to each other by TAHMO network. Those stations are under supervision by science teachers who get a stipend for their work. The weather stations have a built-in SIM- card and are connected with a telecom network, 98% Vodafone telecom network. For students the data is for free to view, so there can be done research to climate change. The data is collected from the stations is saved and then to be converted to a self-funded model where commercial partners pay for the data.


The weather data is measured by several sensors. These sensors measure: rainfall, wind speed, air pressure, GPS, humidity and lightning. The data of these sensors combined give an accurate image of the weather in the area.

The size of the weather station is a cylinder that has a 10 cm diameter and is 20 cm long. There are no moving parts, which makes it easy to maintain and durable at the same time. On the body of the station is a solar panel located. This powers the whole weather station, as it is very energy efficient.

The costs of the TAHMO weather station are $1500 and are owned by the TAHMO foundation. The weather station is very cheap compared to conventional weather station which cost about $20.000, more than 13 times as much. It is still very expensive for Ghanaian farmers to own their weather station, but it is a step in the right direction.


TAHMO is trying to reach the whole continent of Africa. They are trying to do this by speaking with local authorities in every country. This brings several challenges as every country is different. In Rwanda the government understood the TAHMO project and wanted to invest $300.000 immediately, as in Ghana the stakeholders were much more conservative and did not whet the appetite of weather data to improve the harvest of cocoa beans. This is why Farmerline was set up to develop business models to make the weather stations a self-funded system.


This data is saved locally on the station itself every 5 minutes. Every 6 hours, the data is transferred by use of mobile telecom network, GPRS. The data is send to the

conventional phone masts. Which afterwards is sent to the servers in USA named Decagon, so that everyone who is licensed can use it for its own good.


The value of the data is very diffuse. Who would want to pay for this weather data? In the Netherlands the KNMI collects all the weather data and it belongs to the government. However, the KNMI does not deliver all forecasts. There are companies or institutions such as ‘weeronline’ and ‘buienalarm’ in the Netherlands that combine certain data to create a greater value. This is what also can be done in Africa and thus asking a little fee for it.