Abstract
The wettest 2018 long rainy season (March to May (MAM)) resulted in daily intensive rainfall events in East Africa that have seriously affected the environment and economy in many countries. Land subsidence is one of the environmental disasters that has occurred due to the long rainy season in Kenya for many years. However, it has received limited scientific attention. In this paper, we incorporate hydrological (soil moisture active–passive (SMAP) and loading models) and geodetic data (global positioning system (GPS) and interferometric synthetic aperture radar (InSAR)) to study hydrological changes and their associated subsidence potential in Kenya. Results show that widespread subsidence of more than 20 mm was associated with the MAM season in Kenya during 2018, based on SBAS InSAR measurements. The high values of land subsidence were well correlated with the areas of intense flooding during the MAM season. The widespread subsidence during the wet season has implications for the stability of the earth’s surface during the season rather than creating the possibility of potential stresses along active faults. These stresses may trigger seismicity that is expected to pose risks to urban features. The results of the current study can help governmental authorities to adopt proper urban planning that avoids or minimizes the risks of land subsidence in the areas of sinkholes.
Highlights
Following the devastating drought that struck the Horn of Africa for two years (2016–2017), the wettest 2018 long rainy season (March to May (MAM)) resulted in episodes of exceptional rainfall every day [1]
Using the empirical cumulative density functions (ECDF) method, the distribution of the precipitation and soil moisture changes were mapped across the East African countries from January to June 2018
The rate of land subsidence measured from interferometric analysis of the synthetic aperture radar (InSAR) is higher than the estimated rates from both the nearby GPS site and the hydrological loading model
Summary
Following the devastating drought that struck the Horn of Africa for two years (2016–2017), the wettest 2018 long rainy season (March to May (MAM)) resulted in episodes of exceptional rainfall every day [1]. The rainfall events triggered extensive flooding with a notably high impact on society, including a significant number of casualties and the displacement of around one million people. The 2016–2017 drought event was the most notable drought in the last few decades, and it was probably associated with the La Niña conditions This drought event was interrupted by the extensive flooding of the 2018 MAM rainy season, which was the wettest season recorded in 70 years. It is estimated that by 2030, the costs could reach 2.6% per year of the gross domestic product (GDP) of the country [10] In this context, many negative consequences may be triggered by the continuous changes to the hydrological regimes in Kenya, including land subsidence
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
