Lake surface temperature as a proxy of climate change
Lake surface temperature as a proxy of climate change
Satellite observations versus multi probe data
Satellite observations versus multi probe data
S. Pareeth
1,2,4
, M. Metz
1
, D. Rocchini
1
, N.Salmaso
2
, R. Adrian
3,4
, and M. Neteler
1
Introduction - WarmLakes
Sensors and Thermal data
Methods
1
2
3
4
5
Lakes under
study
1. Lake Garda
2. Lake Iseo
3. Lake Como
4. Lake Maggiore
5. Lake Trasimeno
●
Study the long term warming trends of Sub-Alpine lakes using surface
temperature derived from satellite data
●
Leveraging the availability of daily thermal imageries for last 2 decades from
multiple sensors aboard satellites
●
Lake specific validation and model development using field data
●
Develop daily homogenized Lake Surface Water Temperature (LSWT) for last
2 decades.
●
Time series analysis linking the trend with climatic tele-connection index -
Eastern Mediterranean Pattern (EMP)
●
EMP explains well, variation in water surface temperature over Mediterranean
area than NAO (North Atlantic Oscillation)
●
Presenting here the preliminary results for Lake Garda
Global products for daily Surface Temperature
~ 2014 AVHRR June 1991 April 2012 2000 2014~ ATSR/A(A)TSR MODIS 4:36 and 16:36 local solar time
~
~
0130 and 1330 , 10:30 and 22:30 local solar time
10:00 and 22:00 local solar time
~
1980,s 1998
Geocoding issues
MODIS Land Surface Temperature (LST) products
– MOD11A1, MYD11A1 @ 1km , daily 2 observations, from 2002 – Covers all the lakes globally
– 1km spatial resolution
– https://lpdaac.usgs.gov/products/modis_products_table
MODIS Sea Surface Temperature (SST) products
– 4 km spatial resolution, daily 2 observations, from 2002 – few lakes
– http://oceancolor.gsfc.nasa.gov/
AVHRR pathfinder SST products
– 4 km spatial resolution, daily
– Not suitable for Sub-alpine Lakes – longest time series (from 1981)
ArcLakes – Lake Surface Water Temperature(LSWT) from ATSR/AATSR
– 0.05 degrees, 1995 – 2012, daily
– by School of Geosciences, University of Edinburg – daily recostructed data, day and night
– covers1600 lakes globally
– http://www.geos.ed.ac.uk/arclake/
Raw thermal data from
MODIS;A(A)TSR;AVHRR Brightness temperatures
Global LST/SST products
Optimized split window SST algorithm for Lakes Lake Surface Water Temperature (LSWT)
Level 1
(Calibration)G.C. Hulley et al. / Remote Sensing of Environment 115 (2011) 3758–3769 Lake/Sensor specific coefficients (clear sky)
Level 2
Cloud mask /QC layers Statistical Reconstruction MethodsGap filled seamless Time series
data set
Level 3
Validation/Model development using field data
Modeled Time series of LSWT
Level 4
Cloud mask /QC layersMutiple Spatio-temporal regression approach using secondary datasets (Metz et.al, 2014)
– Daily four observations of MODIS LST at 250m for entire Europe – Using hierarchial temporal and spatial interpolation
– Regression model using climatology parameters, Digital Elevation Model (DEM) etc
Harmonic ANalysis of Time series (HANTS) (Roerink et.al)
– Fourier Analysis
– Temporal interpolation
– Implemented in GRASS – “r.hants”
15 17 20 22 25 °C 15 17 20 22 25 °C 0.5 1.2 1.8 2.4 3.0 °C
2003 Summer Mean 2008 Summer Mean
2003-2008 Summer Mean difference
- 2003 – 2013 - MODIS SST
- Reconstructed using HANTS
October 27 2006, MODIS-Aqua – 13:30; Metz et.al, 2014
Raw LSWT Reconstructed LSWT Difference map (raw-reconst)
Results
Reconstruction of time series
Validation
Shortcomings
LST algorithm not suitable for
water surface
Gaps in time series due to clouds and bad raw data
Coarse spatial resolution of
the available products
Scope of using lake/sensor specific coefficients to derive Lake Surface Water
Temperature (LSWT)
Gap Reconstruction Algorithms
GRASS
Open source data processing environment
http://grass.osgeo.org/ http://r-project.org/ LST vs SST (Clear Sky) 7 9 11 13 15 17 19 21 23 25 5 10 15 20 25 f(x) = 1.05x - 0.32 R² = 0.98 Field data M O D IS S S T - 2003 – 2013 - MODIS SST
- Monthly field data
5 7 9 11 13 15 17 19 21 23 25 f(x) = 0.94x + 0.36 R² = 0.95 M O D IS L S T - 2003 – 2013 - MODIS LST
- Monthly field data
-1.5 -1 -0.5 0 0.5 1 1.5 7 9 11 13 15 17 19 21 23 25 5 10 15 20 25 f(x) = 1.03x - 0.09 R² = 0.96 2003 - 2013 monthly Field data M O D IS L S W T -2 -1.5 -1 -0.5 0 0.5 1 1.5 Garda
Trend of daily mean deviation
Lake Garda- MODIS LSWT, 2003 – 2013 daily
Garda
Lake Garda- A(A)TSR - ArcLakes LSWT, 1995 – 2011 daily
p = 0.13 Sen slope = 0.02 p = 0.002 Sen slope = 0.06 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 7.5 8 8.5 9 9.5 10 10.5 f(x) = - 0.35x + 9.2 R² = 0.34 EMP vs LSWT EMP M o d e lle d A T S R L S W T
EMP vs Winter Average Temp from LSWT
Conclusions/Future directions
References
● Thermal imageries from Satellite sensors can measure LSWT accurately, with an overall R
squared above 0.90
● SST algorithms are more accurate for water surfaces than LST based data
● Out of the available products MODIS SST and ArCLakes data (A(A)TSR) performs well. ● Products are of very coarse resolution, not suitable for inter lake studies
● The available products does not have the data for all the sub/alpine lakes
● The negative correlation of satellite derived winter averages with EMP is proven trend
explaining the local variation
● Extending back the database to begin from 1980 using NOAA AVHRR data ● Extending the study to other sub/alpine lakes
● Homogenizing the LSWT data based on Split window SST algorithm and optimized lake specific coefficients (Hulley et.al, 2011) to develop daily LSWT from 1980 - 2013
Metz, M.; Rocchini, D.; Neteler, M. Surface Temperatures at the Continental Scale: Tracking Changes with Remote Sensing at Unprecedented Detail. Remote Sens. 2014, 6, 3822-3840
Glynn C. Hulley, Simon J. Hook, Philipp Schneider, Optimized split-window coefficients for deriving surface temperatures from inland water bodies, Remote Sensing of Environment, Volume 115, Issue 12, 15
December 2011, Pages 3758-3769, ISSN 0034-4257
Roerink, G. J., Menenti, M. and Verhoef, W., 2000. Reconstructing cloudfree NDVI composites using Fourier analysis of time series. International Journal of Remote Sensing, 21 (9), 1911-1917
Salmaso N (2012) Influence of atmospheric modes of variability on a deep lake south of the Alps. Clim Res 51:125-133
MODIS - Moderate Resolution Imaging Spectroradiometer, NASA A(A)TSR - Advanced Along-Track Scanning Radiometer, ESA AVHRR - Advanced Very High Resolution Radiometer, NOAA
1 GIS and Remote Sensing unit, Department of Biodiversity and Molecular Ecology,
The Research and Innovation centre (CRI), Fondazione Edmund Mach (FEM), Trento, Italy
2 Limnology and River Ecology unit, Department of Sustainable Agro-Ecosystems and Bioresources,
The Research and Innovation centre (CRI), Fondazione Edmund Mach (FEM), Trento, Italy
3 Department of Ecosystem Research, Leibniz Institute of Freshwater Ecology and Inland
Fisheries (IGB), Muggelseedamm, Berlin, Germany
4 Department of Biology, Chemistry and Pharmacy, Freie Universität, Berlin, Germany