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Applications for UAVs, HAPs and CubeSats. Presentation by B.Kerridge, RAL CEOI Challenge Workshop 10 th July 2012, University of Nottingham. 1. Introduction. Remit for CEOI Workshop: remote-sensing applications UAVs – Unmanned Aerial Vehicles
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Applications for UAVs, HAPs and CubeSats Presentation by B.Kerridge, RAL CEOI Challenge Workshop 10th July 2012, University of Nottingham
1. Introduction Remit for CEOI Workshop: remote-sensing applications • UAVs – Unmanned Aerial Vehicles • Long duration, high-altitude, large payload, unpressurised eg GlobalHawk: >30hr, ~20km altitude, >1,500lb payload • Long transects, remote or hazardous locations, troposphere & lower stratosphere as well as surface applications • HAPs – High Altitude Platforms • Very long duration, quasi-geostationary, high-altitude, very large payload eg HALE-D: ~months, ~20km altitude →~1,000km diameter field-of-regard • Monitoring of troposphere & lower stratosphere as well as surface • UAVs and HAPs offer high spatial resolution to complement satellite platforms • Satellite engineering practices relevant for these airborne platforms • Suitable for demonstration of future satellite sensors • CubeSats – ~10cm x 10cm x 10cm • Small, lightweight, (inexpensive) sensors with modest requirements (attitude control, thermal control, power, data downlink) • Constellation offers dense geographical coverage
NOAA • “Unmanned Aircraft Systems (UAS) can revolutionize NOAA’s ability to monitor and understand the global environment. There is a key information gap today between instruments on Earth’s surface and on satellites — UAS can bridge that gap.” • “UAS can also collect data from dangerous or remote areas, such as the poles, oceans, wildlands, volcanic islands, and wildfires.” • “Specifically, UAS may: • Extend hurricane landfall lead times by observing storm environments. • Improve accuracy of storm forecasts, • Improve climate change understanding • Assess Arctic ice change and affects on ecosystems and coasts. • Improve flood and drought forecasts • Increase safety and success in fighting wildfires • Monitor coasts, oceans, environments important for fish, and marine sanctuaries”
NASA airborne activities • UAVs feature prominently G-III UAVSAR SMAPVEX12 - 2012 Soil Moisture Active Passive (SMAP) Validation Experiment ECO-3D to provide critical measurements on forest biomass structure and carbon CARVE – Alaskan Arctic 2012 http://airbornescience.nasa.gov/program/current_activities
GreenHouse Observations of the Stratosphere and Troposphere (GHOST) instrument for Global Hawk Compact short-wave IR spectrometer to observe tropospheric column average CO2, CH4, H2O and CO and HDO/H2O over ocean GHOST will use technology similar to NASA’s OCO-II and supported by CEOI (IFU spectrometer) • Science objectives: • test atmospheric transport models (e.g., tropics – subtropics transition zone • validate satellite GHG column observations over oceans, to fill gap in TCCON • complement in situ TTL tracer observations from Global Hawk link upper troposphere with lower troposphere measurements Courtesy, H.Boesch (U.Leicester)
Methane variability June 16, 2011 July 10, 2011 12km Profiles from in situ sensor during ascents & descents in HIPPO flights 0km Aug 19, 2011 Sep 8, 2011 Height-resolved data would improve on column-averages also for surface emissions
Height-resolution from IR spectrometry Global CH4 in the upper and mid troposphere from IASI FTIR ppmv ppmv 178 hPa 422 hPa IASI column average Courtesy A.Waterfall, RAL • Laser Heterodyne Radiometer (CEOI) • Compact IR spectrometer • Heterodyne: very high spectral & spatial resolution • Height-resolved CH4 & see between clouds • Limb-sounder for high-res vertical profiling • in combination with mm-wave (CEOI) Courtesy D.Weidmann, RAL
Volcanic Plumes • Remote-sensors on UAV flying above civil air space could observe: • altitude, thickness & geographical extent of thin volcanic plumes • differentiate ash (from cirrus), sulphate aerosol & SO2 • Complementing: • operational satellite system (nadir-sensors lack height-res) • “AVOID” – ir limb-imager under development for airliners SO2 from Mt.Etna in AVOID test flight courtesy F.Prata (NILU) CMS on TechDemoSat
UAV applications for Cryosphere • Ice thickness (ice penetrating radar) • Grounding line position (repeat pass InSAR)
Ice thickness (ice penetrating radar) • Ice thickness cannot be measured from • existing satellite platforms • Major obstacle for ice sheet models as • cannot resolve ice streams where • instabilities arise • Main complication is available power, • bandwidth, and frequency occupied by • telecoms / millitary • Measurement technique is very simple. • Extent of current data limited to • operations of airborne platforms • UAV platform a major opportunity Existing airborne ice thickness data in Antarctica. Ice sheet models run at 5 km resolution Courtesy of A.Shepherd
2. Grounding line position (repeat pass InSAR) • Grounding line is junction • between ice, bedrock, and ocean • GL migration rate is a key • indicator of ice sheet stability • GL can be located using repeat • pass InSAR due to tidal flexure of • floating ice • No current or future satellite • sensors can deliver • UAV repeat pass InSAR system • could provide early warning of ice • sheet collapse Grounding Line mapped by InSAR (Rignot, 1998) Courtesy of A.Shepherd
3. HAPs: Quasi-Geostationary Platform in Stratosphere Bridge the gap in scales between surface sensors & satellites
Geostationary orbit ~36,000km E Polar orbit ~900km View from 20km altitude Greater London & Thames estuary Atmospheric Composition
Pollution Monitoring: Tropospheric NO2 over Europe from OMI (Dec’04-Nov’05) Courtesy, P.Levelt (KNMI) • Information above and between surface networks • Relevance for annual emissions inventories
Remote-sensing of NO2 • Imaging DOAS now used to map NO2 • CompAQS developed within CEOI • Used from ground in CityScan system • (eg over London during Olympics) • Could be mounted on UAV or HAP City Centre Airport
Airborne Imaging of NO2 over Zurich by Swiss and Belgians 10am 5:30pm Annual average model NO2 concentration NO2 vertical column density Courtesy, R.Leigh (U.Leicester)
HALE-D • Lockheed Martin launched HALE-D on July 27, 2011 • Demonstrating key technologies critical to development of unmanned airships. • Altitude 60,000 feet
Radio Occultation Temperature & humidity profiling from radio occultation bending angle FORMOSAT-3/COSMIC joint Taiwan/US mission launched 14th April 2006 • 6 identical micro satellites carrying advanced GPS radio occultation (RO) receiver, a Tiny Ionospheric Photometer (TIP), and a Tri-Band Beacon (TBB). FORMOSAT-7/COSMIC-2 • 6 satellites into low-inclination orbits in early 2016 • 6 satellites into high-inclination orbits in early 2018. • Global Navigation Satellite System (GNSS) RO payload, TriG (Tri-GNSS), will be capable of tracking 12,000 profiles per day once both constellations deployed. GNSS constellations: GPS and Galileo [R] and [G], GLONASS and BeiDou [G] MetOp-SG: improved performance cf GRAS on MetOp • L1(1575.42MHz) and L5(1176.45MHz) frequency selection compatible with GPS and Galileo and will be compatible with future GLONASS and BeiDou in 2020 timeframe • 8-fold increase in acquisitions
Surface Reflectometry • GPS reflections possible from ocean, ice and land surfaces • Received signal is“affected” by surface type and traversed atmosphere • Possibility to use reflected signal for sea surface topography, wind vector • (or “roughness”), ice topography/thickness, soil moisture, eg TechDemoSat
5. Summary • UAVs, HAPs & CubeSats have great potential for remote-sensing • Range of applications spans EO disciplines: • atmosphere, land surface, ocean, cryosphere • Relevant sensors potentially include CEOI technology: • Compaqs (uv/vis), GHOST(swir), LHR (ir) & mm for atmospheric composition; canopy lidar • UAV for long flights, at high-altitude, with access to remote or hazardous locations • eg forests, polar ice, storms/hurricanes, volcanic plumes • GlobalHawk prominent in NASA & NOAA campaigns (including lidar & SAR), targeted by NERC CAST and also potential alternative to Geophysika for UTLS limb-sounding • HAP attractive future platform for monitoring on regional scale • eg pollution, surface emissions, vegetation stress, soil moisture & soil temperature; agriculture; hydrology (flooding); coastal zone • CubeSat constellations offer dense coverage • eg GNSS RO profiling and sea-surface reflectometry