Breakthrough: The Lake Sentinel

This video is a part of Breakthrough, a short film anthology from Science Friday and Howard Hughes Medical Institute (HHMI) that follows women working at the forefront of their fields. Learn more and watch the films on our Breakthrough spotlight.

Growing up in rural Guatemala, Africa Flores-Anderson was used to seeing unregulated agricultural runoff and polluted waterways. She thought that all landscapes in her country were laden with contaminated waters. When she went to live in western Guatemala where the land is less farmed, she saw for the first time healthy rivers, lakes, and forests. It was the moment Flores-Anderson decided to dedicate her life and education to environmental sciences and sustainability. To help underserved communities like the one she grew up in, Flores-Anderson focused her studies on learning how to collect and interpret satellite data across huge landscapes and waterways

a woman sits in front of a laptop with a satellite image of a lake and she speaks to a table of fellow scientists
Credit: © Science Friday

“From space, I can see the forest and the condition of that forest, and I can see the river and the water quality of that river,” she says. “It completely revolutionized my world of the work I was doing.”

Today, she works as an earth scientist and regional coordinator for the SERVIR (a collaborative NASA and USAID project), where she models environmental changes in regions without science infrastructure and resources. Her work helps decision-makers visualize fire, industrial, or disaster damage, predict future risks, and influence the allocation of development funds. In addition to this work, Flores-Anderson acquired funding to monitor the water quality of Guatemala’s Lake Atitlán, a source of drinking water, fishing, irrigation, and tourism.

Lake Atitlán is known for its pristine waters, but Flores-Anderson has been monitoring recurring harmful algal blooms. Using her GIS skills, Flores-Anderson is mapping the levels of cyanobacteria in the lake over time and finding correlations with agricultural activity on the lake’s banks. With these advanced tools, she wants to identify the severity of the problem and pass insights on to local authorities to allow them to save Atitlán from the fate of the degraded landscapes of her youth.

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Directed and Produced by Katie Garrett

Director of Photography –  Katie Garrett and Michelle Lotker

Edited by Erika Sutter and Katie Garrett

Animations by Luke Groskin

Satellite Data Provided by Africa Flores Anderson

Music by Audio Network On-Location

Production Support Rudy Augusto Flores Cano

Series Producer Luke Groskin Landsat4, 5, 6, 7, and 8 Images Courtesy of the U.S. Geological Survey Copernicus Sentinel 1 and 2 Images Processed by the European Space Agency.

Additional Satellite Images by SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE Matthew R. Radcliff, James R. Irons, Cindy Starr, Rachel Kreutzinger NASA Earth Observatory image by Jesse Allen, Level 1 and Atmospheres Active Distribution System (LAADS)

Additional Photos and Video Provided by Shutterstock

Project Advisors for HHMI Tangled Bank Studios Richard Stone Aileen O’Hearn

Project Support for Science Friday Initiative Danielle Dana, Jennifer Fenwick, Ariel Zych Nadja Oertelt, Kyle Marian Viterbo, Diana Montano Daniel Peterschmidt, Xochitl Garcia, Nahima Ahmed

Special Thanks Rudy A. Flores Cano · Rudy A. Flores Cordova Eva de la Luz Cordova Sanchez de Flores Claudia Suseth Romero Oliva · Margaret Dix Jorge Jose Garcia · Molly Porter Universidad del Valle de Guatemala Universidad de San Carlos University of Alabama in Huntsville NASA-Marshall Space Flight Center

Meet the Producers and Host

About Katie Garrett

Katie Garrett is a filmmaker, biologist, photographer, and artist. She has produced film pieces for National Geographic, Geographical Magazine (Royal Geographical Society), bioGraphic (California Academy of Sciences), Ensia, and Operation Wallacea. 

About Luke Groskin

Luke Groskin is Science Friday’s video producer. He’s on a mission to make you love spiders and other odd creatures.

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