developing a self-adjusting algorithm to detect significant changes in water use efficiency and net primary production

In the latest issue of Big Earth Data

Abstract: Monitoring changes in Annual Net Primary Productivity (ANPP) is required for reporting on UN Sustainable Development Goal (SDG) Indicator 15.3.1: the proportion of land that is degraded over the total land area. Calibrating time-series observations of ANPP to derive Water Use Efficiency (WUE; a measure of ANPP per unit of evapotranspiration) can minimize the influence of climate factors on ANPP observations and highlight the influence of non-climatic drivers of degradation such as land use changes. Comparing the ANPP and WUE time series may be useful for identifying the primary drivers of land degradation, which could be used to support the Land Degradation Neutrality objectives of the UN Convention to Combat Desertification (UNCCD). This paper presents an algorithm for the Google Earth Engine (freely and openly available upon request – http://doi.org/10.5281/zenodo.4429773) to calculate and compare ANPP and WUE time series for Santa Cruz, Bolivia, which has recently experienced an intensification in its land use. This code builds on the Good Practice Guidance document (version 1) for monitoring SDG Indicator 15.3.1. We use the MODIS 16-day average, 250 m resolution to demonstrate that the Enhanced Vegetation Index (EVI) responds faster to changes in water availability than the Normalized Difference Vegetation Index (NDVI). We also consider the relationships between ANPP and WUE. Significant and concordant trends may highlight good agricultural practices or increased resilience in ecosystem structure and productivity when they are positive or reducing resilience and functional integrity if negative. The sign and significance of the correlation between ANPP and WUE may also diverge over time. With further analysis, it may be possible to interpret this relationship in terms of the drivers of change in plant productivity and ecosystem resilience.

Read the full article here.

Since our 2022 Biennial Meeting and with the expert leadership of an ad hoc Governance Committee, GEOAquaWatch has simplified and streamlined our Working Group structure and created a new Code of Conduct for our membership.   These efforts build off the recent formation of our Early Career Society, update the long-established Management Team and Steering Committees, and implement our DEI Policy Initiative-wide.

With these modifications and improvements, GEO AquaWatch hopes to better reflect the diverse global water quality community.

We are also excited to have finished that reorganization process and to get on to the fun activities we’ve been brainstorming in our Users and Technical Working Groups.

UN Environmental Program, in partnership with Deltares, Group on Earth Observations (GEO) Secretariat, Secretariat of the Convention on Wetlands, GEO AquaWatch, GEO BluePlanet, GEOHealth, EO4SDGs, Brockmann Consult, and GEOGloWS is hosting this 90 minute virtual official side event for the UN Water Conference.  

The goal of this side event is to introduce Member States and interested parties to the utility of Earth Observations for water monitoring and identify cross-sectoral partnerships that can support the Water Action Agenda. 

Date: March 20, 2023

Time: 10:00-11:30 EDT (14:00-15:30 UTC)

Register to Attend: 

View the latest speaker agenda and find out more both before and after the event by clicking here!

The William T. Pecora Award is presented annually to individuals or groups that have made outstanding contributions toward understanding the Earth by means of remote sensing.  The Department of the Interior (DOI) and the National Aeronautics and Space Administration (NASA) jointly sponsor the award.

The award was established in 1974 to honor the memory of Dr. William T. Pecora, former Director of the U.S. Geological Survey and Under Secretary, Department of the Interior.  Dr. Pecora was a motivating force behind the establishment of a program for civil remote sensing of the Earth from space.  His early vision and support helped establish what we know today as the Landsat satellite program.

The Award Committee must receive nominations for the 2023 award by May 1, 2023.  Additional information can be found at here or on the attached flyer; and questions can be directed to the Committee at pecora@usgs.gov

Flyer