CAPTURING DEVILS IN THE DESERT

SCIENCE GOALS AND OBJECTIVES - DUST DEVILS MAY DOMINATE THE SUPPLY OF DUST IN THE MARTIAN ATMOSPHERE INFLUENCING THE ATMOSPHERIC HEAT BUDGET AND CLIMATE BUT THEIR EXACT DUST CONTRIBUTION REMAINS HIGHLY UNCERTAIN. WE PROPOSE TO ANALYZE PREVIOUSLY COLLECTED DATA AND OBTAIN NEW DATA USING AN INSTRUMENTED DRONE TO MAP THE PRESSURE TEMPERATURE WIND AND DUST DENSITY PROFILES OF DUST DEVILS AND UNDERSTAND HOW TO TRANSLATE OBSERVATIONS OF DEVILS MADE ON MARS INTO ATMOSPHERIC DUST FLUX ESTIMATES. THE TWO PROPOSED PROJECTS WILL EMPLOY AND IMPROVE UPON TECHNIQUES ALREADY PROVEN BY OUR GROUP IN THE FIELD INCLUDING A PILOT STUDY DURING WHICH WE SUCCESSFULLY PROBED ACTIVE DUST DEVILS USING A SMALL QUADCOPTER. METHODOLOGY - FOR PROJECT (1) WE WILL ANALYZE DATA ALREADY COLLECTED FROM A PREVIOUS DEPLOYMENT OF METEOROLOGICAL SENSORS AT LA JORNADA PLAYA (LORENZ 2016). THIS SENSOR ARRAY INCLUDING BAROMETERS AND PHOTOMETERS PROVIDES A RICH DATA SET AND LORENZ (2016) RECOVERED ABOUT TWO DOZEN DUST DEVIL EVENTS. THAT STUDY'S ANALYSIS PROVIDED INITIAL CONSTRAINTS ON THE POSITION AND VELOCITY VECTORS FOR ONE SUCH EVENT. FOR THIS PROJECT WE WILL ANALYZE THESE DATA TO FIND MORE EVENTS USING OUR PREVIOUSLY DEVELOPED DETECTION ALGORITHM (JACKSON&LORENZ 2015). WE WILL ALSO APPLY A NEWLY DEVELOPED SCHEME TO MAP THE STRUCTURES AND TRAJECTORIES OF DETECTED DEVILS WHICH SIDESTEPS THE USUAL UNCERTAINTIES RELATED TO THE UNKNOWN ENCOUNTER GEOMETRY. FOR PROJECT (2) WE WILL CONDUCT NEW FIELD SURVEYS ON THE ALVORD DESERT IN SOUTHEASTERN OREGON AND ON EL DORADO PLAYA IN NEVADA USING AN INSTRUMENTED DRONE. FOR THIS EFFORT WE WILL EQUIP A COMMERCIALLY AVAILABLE DRONE WITH A PRESSURE AND TEMPERATURE LOGGER TO FLY INTO ACTIVE DUST DEVILS AT A VARIETY OF ALTITUDES. THE DRONE WILL ALSO CARRY A LARGE ADHESIVE STRIP TO PROBE THE DUST COLUMN ABUNDANCE SIMILAR TO PREVIOUS GROUND-BOUND FIELD STUDIES. WHILE THE DRONE IS COLLECTING DUST IN-SITU WE WILL ALSO VIDEO DEVIL ENCOUNTERS USING STEREO-IMAGING. WE WILL THEN CONDUCT A POST-HOC ANALYSIS OF THESE VIDEO IMAGES TO ESTIMATE THE ENCOUNTER GEOMETRY AND THE DUST DEVIL PARAMETERS INCLUDING DIAMETER HEIGHT AND DUST COLUMN ABUNDANCE. RELEVANCE TO SSW - THIS PROPOSAL IS CLEARLY RELEVANT TO NASA'S SOLAR SYSTEM WORKINGS PROGRAM SINCE IT SEEKS TO ``[I]DENTIFY AND INVESTIGATE VARIED FEATURES OF SOLAR SYSTEM ATMOSPHERES'' -- WE WILL INVESTIGATE TERRESTRIAL DUST DEVILS AS ANALOGS FOR MARTIAN DUST DEVILS. OUR WORK WILL ALSO HELP ``[C]HARACTERIZE VERTICAL STRUCTURE AND THE TRANSPORT OF MASS AND HEAT'' BY DUST DEVILS WHICH ACT AT THE SMALLEST SCALES. THEY ARE ALSO ONE OF THE MOST IMPORTANT ``EFFECTS OF COUPLING WITH PLANETARY SURFACES'' AND THE ATMOSPHERE ON MARS.