Investigating temporal relationships between rainfall, soil moisture and MODIS-derived NDVI and EVI for six sites in Africa

Summary, in English

This study investigates temporal relationships between vegetation growth, rainfall, and soil moisture for six sites located in sub-Saharan and southern Africa for the period 2005-2009. Specifically, seasonal components of time series of Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) composites from the Moderate Resolution Imaging Spectroradiometer (MODIS) and half-hourly in-situ rainfall and soil moisture data at different depths (5-200 cm) during the growing season were used in a lagged correlation analysis in order to understand how vegetation growth responds to rainfall and soil moisture across different sites. Results indicate that both vegetation indices are strongly related to soil moisture (EVI slightly stronger than NDVI) for the upper 1 m reaching maximum correlations when they lag soil moisture by 0-28 days. They respond to rainfall with a 24-32 day lag at the sub-Saharan sites, EVI slightly earlier than NDVI, but their response at the southern hemisphere sites is complex.

• Author: Sadegh Jamali; Jonathan Seaquist; Jonas Ardö; Lars Eklundh
• Department/s: Dept of Physical Geography and Ecosystem Science; MERGE: ModElling the Regional and Global Earth system
• Publishing year: 2011
• Language: English
• Full text: - 327 kB; Download statistics
• Links: https://www.isprs.org/proceedings/2011/isrse-34/211104015Final00443.pdf
• Document type: Conference paper
• Topic: Physical Geography
• Keywords: vegetation; soil moisture; hydrology; MODIS
• Conference name: 34th International Symposium on Remote Sensing of Environment - The GEOSS Era: Towards Operational Environmental Monitoring
• Conference date: 2011-04-10 - 2011-04-15
• Conference place: Sydney, NSW, Australia
• Status: Published