Invest more in irrigation schemes, this is crucial

JKUAT students from left to right Martin Bakuni, Allan Mwangi and Pramilla Nekesa harvest indigenous vegetables grown under sensor irrigation machine. [Jenipher Wachie, Standard]

Kenya’s weather patterns are changing. The change in rainfall patterns has a huge impact on Kenya because 98 per cent of the country’s agriculture is rain fed. The major challenge that farmers face is timing. It is critical for them to know when rains start and stop so that they know when to plant or harvest their crops.

Most parts of Kenya experience two rain seasons; March to May’s long rains and October to December’s short ones. The months of June to August are mainly cool and dry over most parts of the country, except for some areas in the western region that get rain.

Hot and dry conditions are normally observed in the entire country in January and February. In recent years, delay in the coming of rains has been the norm. In other years, rains came on time but then stopped earlier than anticipated. Such lead to massive crop failures.

Other than rainfall patterns, studies show a reduction in the amount of rainfall, especially during the March to May long rains' period. This is a worrying trend, given that this is the main planting season.

The changes in Kenya’s rainfall patterns have been linked to climate change. Global warming is known to cause an overall warming in the atmosphere and the ocean, resulting in complex shifts that affect our planet’s weather and climate systems. Research shows that rainfall is reducing while temperatures are on the rise in Kenya, as is the case in other countries in the Horn of Africa.

Delayed rains

In the case of Kenya’s delayed rains, another culprit has also been identified; cyclones. It is normal for cyclones to happen on the southern African coast between February and March. But their magnitude is dictated by sea surface temperatures. These warm as a result of increased emission of greenhouse gases in the atmosphere, leading to global warming. This means the intensity and frequency of cyclones is likely to increase.

The most recent cyclone was Idai and it occurred in the western Indian Ocean in March last year. The cyclone caused a depression – low pressure zone – in the ocean, cutting off moisture from flowing from the southern hemisphere to East Africa. Cyclone Idai delayed the northward progression of the rain-bearing low pressure zone, also known as the Inter-Tropical Convergence Zone.

This limited the moisture flow from reaching Kenya, leading to the observed seasonal rainfall delay that strengthened anomalous dryness from early mid March last year. A combination of failed rainfall and the observed high temperatures adversely impact agricultural activities across many parts of the country.

Because Kenya’s economy relies heavily on rain-fed agriculture, it has to be prepared. Agriculture also accounts for 70 per cent of the workforce and about 25 per cent of the annual GDP. In the short term, the country relies on food reserves. This is mainly maize stored by the National Cereals and Produce Board. Unfortunately, with conflicting statements, it’s not clear just how prepared the government is and how much is actually in the reserve.

In the long term, the country is not doing enough to respond to these changing rainfall patterns. Given that drought is not new in Kenya and is not going away any time soon, one would expect to see large scale water harvesting operations such as what African Water Bank is doing in Narok. We would hope that available food resources were being properly utilised, too, but the reality is that a lot of food is ending up as waste.

Pilot projects

Research institutions like the Kenya Agricultural Livestock Research Organisation and the International Livestock Research Institution are working hard to come up with drought tolerant crop varieties – but more needs to be done.

The government must put measures in place that reduce the agricultural sector’s over-dependence on rain-fed agriculture. The easiest way is to invest in irrigation infrastructure. This enhances food security, increasing the country’s resilience to the effects of climate variability and change. This has been tried before and pilot projects have been successful. They now need to be systematically rolled out.

Kenya must invest more resources in the climate sector. It must train experts and provide the necessary tools for carrying out regional climate projections.

There also needs to be a clearer picture of the projected climate. Existing climate projections are based on Global Circulation Models that fail to capture the entire East Africa climate. Reports from Intergovernmental Panel on Climate Change and regional studies, for instance, show that over the last 13 years, rainfall was projected to increase in East Africa. But we have seen that the opposite is true.

Mr Ongoma is a Lecturer in Physical Geography, The University of the South Pacific