Public-health applications in remote sensing

Abstract

Remote sensing of the environment is critical to warn of imminent, life-threatening dust storms and to reduce risk of exposure to desert dust and hitchhiking bacteria, molds, heavy metals, and other human-health concerns. Desert dust affects cardiovascular and respiratory illness. Respirable particulates result in health-care costs exceeding $11.5 billion annually, with an additional $4.6 billion for lost productivity.1 As part of the NASA-sponsored Public Health Applications in Remote Sensing (PHAiRS) project, data from NASA’s Terra satellite are assimilated into a numerical-dynamical model of dust generation and entrainment, DREAM (Dust Regional Atmospheric Model). Originally developed for the Mediterranean region2 and modified in PHAiRS for the southwestern United States,3 DREAM is driven by operational weather-forecast models of the US National Weather Service (the Nonhydrostatic Mesoscale Model, NMM, and the operational model it replaces, eta). The DREAM system simulates and predicts—up to three days in advance—the onset of dust storms and the 3D size-concentration characteristics of the resulting airborne-dust clouds. Current barren-ground input to the model consists of MOD12 classification (an International Geosphere-Biosphere Programme ecosystem descriptor of land-cover type and dynamics) condensed to a two-class product: bare ground=1 and all other classes=0. Using Moderate Resolution Imaging Spectroradiometer (MODIS) products to replace the bare-ground class from the Olson World Ecosystem Land Cover map—the model’s original design parameter (see Figure 1)—improved DREAM’s performance significantly (see Figure 2).4, 5 Working with New Mexico’s Environmental Public Health Tracking System, we developed a Web-based client server (see Figure 3) to assist asthma andmyocardial-infarction surveillance Figure 1. (left) Olson World Ecosystem ‘barren’ category. (right) MOD12 (land-cover type and dynamics)-classified ‘barren’ category.