1st IAA Latin American Symposium on Small Satellites: Advanced Technologies and Distributed Systems A SEGMENTED ARCHITECTURE APPROACH TO PROVIDE A CONTINUOUS, LONG-TERM, ADAPTIVE AND COST- EFFECTIVE GLACIERS MONITORING SYSTEM C. Barrientos (1), A. Ferral (1), L. Cara (1), J. Fraire (2), R. Velazco (2), P. Madoery (3), P. Ferreyra (3). (1) Comisión Nacional de Actividades Espaciales (3) LCD and LCSR Laboratories, Universidad Nacional de Córdoba (2) TIMA Laboratoire, CNRS, Université Grenoble-Alpes
Motivation Climate change is the biggest challenge facing humanity in its whole history Dr. Mario Molina, Nobel Prize in Chemistry 1995 Green Economy Latin American Congress, Córdoba, Argentina Dec 2016 08/03/2017 Glacier SOS 2
Sentinels of Climate Change 08/03/2017 Glacier SOS 3
Numer of papers Is there Scientific Consensus? 1000 900 800 700 From: SCOPUS Database cl. change cl. change AND glacier cl. change AND remote sensing cl. change AND glacier AND remote sensing Total papers =245,502 600 500 400 Total papers = 5,766 300 200 100 1849 1934 0 1820 1840 1860 1880 1900 1920 1940 1960 1980 2000 2020 2040 Year 1987 Total papers = 449 08/03/2017 Glacier SOS 4
Glaciers spread across the Globe 130.000 glaciers distributed around the globe. Source: GLIMS database 08/03/2017 Glacier SOS 5
Although Poorly Monitored Source: World Glacier Monitoring Services 08/03/2017 Glacier SOS 6
Data from 40 Reference Glaciers Source: Global Cryosphere Watch 08/03/2017 Glacier SOS 7
Difficult Field Campaigns From: IANIGLIA/CONICET (Glaciar de los Tres, Argentina) 08/03/2017 Glacier SOS 8
Can data be Uploaded to S/C? Upload to spacecrafts Autonomous Power Solar radiation Wind Speed Size of a DCP acquisition including auxiliary data = 40 bytes.. Frame rate for uploading a DCP frame to the satellite = 400 b / s Maximum uploading time = 1 [s]. Collect & Store Data Humidity Rain Black Carbon 08/03/2017 Glacier SOS 9
Glacier SOS Proposal The main objective is to provide a continuous, long-term, responsive, adaptive, scalable and cost-effective Glacier Segmented Observation System (SOS) in order to provide information on a global scale, with high revisit time and under homogeneous conditions for studies related to: Climate change, Glacier meteorology, Black carbon deposition on glaciers, Mass balance and glacier dynamics assessment. Mission Architect: Carlos Barrientos (CONAE) Principal Investigators: Anabella Ferral (CONAE) y Leandro Cara (CONAE) Segmented Architecture: Juan Fraire (UNC/UGA), Pablo Ferreyra (UNC) 08/03/2017 Glacier SOS 10
System Requirements R.01 The system shall provide uninterrupted, continuous service to users for a life span of at least 30 years. R.02 The system shall be cost-effective, based on the use of standard commercial off the shelf (COTS). R.05 The system shall have on site sensors in order to gather and upload to the system the following information: (1) Meteorology data. (2) Black carbon deposition data. (3) Mass displacement data. R.06 The system shall have a number of sensors on board the flight segments in order to: (1) Acquire High-Resolution images and (2) Store and forward data from other sensors that are part of the system. 08/03/2017 Glacier SOS 11
System Requirements R.03 The System shall address the full extension of glaciers geographical distribution in latitudes from -80 to +80 degrees. R.04 The system shall gather reflectance information from different glaciers under homogeneous conditions in terms of ground resolution, swath and sunlight incidence angle. R.07 The system shall be protected to technological obsolescence and shall adapt to new emerging technologies in remote sensing, sensor devices and communications R.08 The system shall have updated information of glaciers on a global scale and with a revisit time of not less than 24 hours. R.09 The system shall have a scientific scope generating glaciers monitoring data and related value-added products, available to the scientific community in a regular basis. 08/03/2017 Glacier SOS 12
On ground Segments On ground Segments Modules located on glaciers for collecting scientific data Module located on ground to provide a data-relay functionality 08/03/2017 Glacier SOS 13
Flight Segments Inter Satellite Link (ISL) network Flight Segments 08/03/2017 Glacier SOS 14
Flight Segment C C&DH Link with Other S/C Actuators Orb. Determ & Attitude Control Electrical Power Link with Ground Station Sensors 08/03/2017 Glacier SOS 15
Proposed Orbital Scenario N = 8 Satellite clusters over sun-synchronous orbits @700 Km. M = 3 nodes clusters. Intra-cluster coms: permanent (ISLdist = 100Km) Inter-cluster coms: sporadic (over the pole) Cluster formation: M N M (+func. and reliabl.) N (+cov. and revisit) #A: Data collection system #B: Multi spectral camera (Black carbon) & displacement detector #C: HS Down Link (coms with ground) 08/03/2017 Glacier SOS 16
Ground Tracks 08/03/2017 Glacier SOS 17
Inter-Cluster Contact Windows 1 2 3 4 08/03/2017 Glacier SOS 18
Contact Opportunities Assuming ISL can work at 500 Km (low data-rate) Inter-cluster coms: sporadic (over the pole) 24 hs 2 hs Intra-cluster coms: permanent (ISLdist=100Km) All #A:, #B: and #C: can talk to the other trains via the ISL 08/03/2017 Glacier SOS 19
Key Advantages 08/03/2017 Glacier SOS 20
Sensor Diversity network node for gathering data from stations located on glaciers optical sensor for measuring reflectance (i.e. black carbon) gateway for communicating with Ground Station 08/03/2017 Glacier SOS 21
Preliminary Characteristics Network node for gathering data from stations located on glaciers Optical sensor for measuring reflectance (i.e. black carbon) Multispectral Sensor for BC Gateway for communicating with Ground Station 08/03/2017 Glacier SOS 22
Black Carbon Importance Bond et. al. JOURNAL OF GEOPHYSICAL RESEARCH: ATMOSPHERES, VOL. 118, 1 173 (2013) 08/03/2017 Glacier SOS 23
Snow Albedo Simulations From: SNICAR Model bands located @ atmospheric windows MS Camera Bands 08/03/2017 Glacier SOS 24
System Structure System Control focused on maintaining the satellite constellation alive focused on science data & applications 08/03/2017 Glacier SOS 25
Mission Center Generating value-added products Scheduling science operations Storing products Technical support, policies and regions of interest Getting raw data Portal for browsing, requesting & retrieving data Distributing Products 08/03/2017 Glacier SOS 26
Control Center Format commands & Process telemetry plan new acquisitions Evaluate orbital param. preserve the flight segments state-of-health process collision alerts send commands to the flight segments 08/03/2017 Glacier SOS 27
Conclusions Lifetime. 30+ years horizon necessary for longitudinal data-series of glaciers variables. Revisit. Depending on the number of clusters, global glacier data could be gathered on an hourly basis. Upgradability. New type of sensors or technological advances added by simply launching a new segment. Scalability. Reliability (and revisit time) of the system could be improved by means of the network size. Cost/benefit. The use of CubeSats allows for a lowcost platform and launch (at least for initial clusters). 08/03/2017 Glacier SOS 28
Path-Finding Work Assessing DTN Architecture Reliability for Distributed Satellite Constellations: Preliminary Results from a Case Study J. Fraire, P. Ferreyra IEEE - 2014 FS2017: An Opportunity to Train Students in Science & Space Technologies IAA-LA-17-P04 Design of a NIR-SWIR Imaging System for Small Satellites IAA-LA-17-P18 08/03/2017 Glacier SOS 29