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Lake surface temperature as a proxy of climate change: satellite observations versus multi probe data

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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 Methods

Gap filled seamless Time series

data set

Level 3

Validation/Model development using field data

Modeled Time series of LSWT

Level 4

Cloud mask /QC layers

Mutiple 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

Riferimenti

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