A new study, published in Scientific Reports, warns that environmental droughts—those affecting ecosystems and biodiversity—are intensifying faster than other types of drought.
The research, which analysed 42 years of data, calls for Nigeria to adopt a multi-index drought monitoring system to better detect and respond to cascading drought risks.
“Environmental droughts are accelerating disproportionately under climate stress, yet they remain the least monitored,” said Dr Aman Srivastava, lead author of the study.
The report reveals some key findings relevant to Nigeria. According to the report, severe environmental droughts have surged by 65%, now accounting for over 36% of all drought events.
In Nigeria, this trend poses a threat to critical ecosystems, such as the Hadejia-Nguru wetlands and the Lake Chad basin. “Our findings show that ecological water deficits are not just seasonal—they’re becoming chronic,” Srivastava noted.
Similarly, streamflow deficits are rising, with severe hydrological droughts doubling in frequency. For instance, rivers in northern Nigeria, such as the Sokoto and Yobe, are increasingly unable to meet ecological flow requirements.
“Hydrological droughts now affect nearly two-thirds of dry-season months. This has serious implications for water security,” the study states.
Agricultural Buffering vs. Ecological Collapse
The research suggests that moderate agricultural droughts are declining, likely due to the adoption of adaptive farming practices. However, environmental systems lack such buffers, leading to biodiversity loss and habitat degradation.
“Agriculture can adapt. Ecosystems cannot,” Srivastava emphasised. “That’s why environmental droughts must be tracked independently”.
Strategic Implications for Nigeria
Current drought monitoring tools used by NIMET and NIHSA focus on rainfall and crop stress but overlook ecological impacts.
Environmental droughts are now the most persistent, lasting over 5 months per event on average.
Single-index systems miss up to 48% of drought cascades, where one type of drought triggers another.
Recommendations
It’s high time Nigeria adopted a Multi-Index Monitoring Integrated SPAI (rainfall), VHI (vegetation), SSI (streamflow), and EDI (ecosystem stress) into Nigeria’s drought early-warning systems.
The government should protect ecological hotspots by prioritising environmental drought metrics in managing Lake Chad, Hadejia-Nguru wetlands, and forest reserves.
Additionally, it should tailor sectoral responses by using index-specific insights to guide irrigation, reservoir releases, and ecosystem restoration.
The government should also invest in data infrastructure and expand satellite and streamflow monitoring in semi-arid and ecologically sensitive regions.
Conclusion
This study offers a replicable model for Nigeria to strengthen its drought resilience. As Srivastava concludes: “We must stop treating drought as a single-sector problem. It’s a multi-system threat—and environmental drought is the blind spot we can no longer afford”.
