Structural Interrelationships of the Evaporation-Precipitation Satellite-based Fields:

Application of the Complex Networks

By Irina Petrova 1,2*

Alexander Löw 1, Christian Klepp 1,2

1 Max-Planck Institute for Meteorology, MPI, www.mpimet.mpg.de

2 Meteorological Institute, KlimaCampus, University of Hamburg,Hamburg, Germany

* Irina.Petrova@zmaw.de

EGU: 25Apr2012, Wed

1

Goals and Objectives:

1. Analyze topology of the single/ coupled precipitation and evaporation networks

2. Investigate the prominent global teleconnection patterns in the constructed networks

3. Identify physical properties within the Climate Networks fields

2

2

3

d(1,3)

d(2,3)

1

Datasets and Experimental Setup:

1

Datasets used::

HOAPS: Hamburg Ocean Atmosphere Parameters and fluxes from Satellite data [http//:www.hoaps.org]GPCC: The Global Precipitation Climatology Center [http//:www.gpcc.dwd.de]

HOAPS(satellite, ocean)

1987-2005

HOAPS-3(ocean)

GPCC(gauge, land)

Precipitation• T63 (1.8)• Monthly • 1992-2005• 13834 vertices

Evaporation• T63 (1.8)• Monthly • 1992-2005• 7968 vertices

3

Datasets and Experimental Setup:

1

Datasets used::

HOAPS: Hamburg Ocean Atmosphere Parameters and fluxes from Satellite data [http//:www.hoaps.org]GPCC: The Global Precipitation Climatology Center [http//:www.gpcc.dwd.de]

HOAPS(satellite, ocean)

1987-2005

HOAPS-3(ocean)

GPCC(gauge, land)

Precipitation• T63 (1.8)• Monthly • 1992-2005• 13834 vertices

Evaporation• T63 (1.8)• Monthly • 1992-2005• 7968 vertices

4

CCN Construction:

5

Model used:: PYCLIMATENETWORK: [J.F Donges et al. 2009]

Single/ Coupled Evap-Precip Networks:

• Similarity Criteria: - Pearson correlation (zero lag) - Spearman rank (zero lag)

• Threshold: 99,9% significance level (t-test)

Correlation values of the ICTZ location neighbours within the Precipitation Network

Teleconnection Patterns: ENSO

Degree Centrality field of the Precipitation Network

6

Source - point

Correlation of monthly mean Dec-Mar precipitation with the station-based NAO index [Andersson et al. 2010]

7

Teleconnection Patterns: NAO+ and NAO-

Degree centrality of the precipitation network [Dec-Mar] Thrsh=0.43

Correlation of monthly mean Dec-Mar precipitation with the station-based NAO index [Andersson et al. 2010]

8

Teleconnection Patterns: NAO+ and NAO-Positive Correlations within the precipitation network [Dec-Mar]

of the neighbours at two locations: Bergen (Norway) and Gibraltar

1

9

Cross Degree Centralities of coupled Precipitation-Evaporation Networks (thresh. = 0,25)

Coupled EVAP-PRECIP Fields:Evaporation Precipitation

1

Downstream Source Feature:Precipitation field: Receiver - point

Correlation Values of the Precipitation Neighbours Within the Evaporation Field and Cross-Degree Centrality (background filed) (Thrsh=0,25)

10

Outlook: Conclusions and Expectations

11

1. Evap-Precip Network structure resembles major teleconnection patterns

2. High DC coupled evap-precip fields reveal spatial source-receptor feature

3. Statistical analysis operation V.S. CCN physical features (Surrogate data, Transfer Entropy)

4. Comparison/ validation of the CMIP5 ESM-MPI using HOAPS dataset

2

3

d(1,3)

d(2,3)

1

Acknowledgements:

The author is grateful for the fruitful collaboration, information and PYCLIMATENETWORK software support to the Potsdam Institute for Climate Research (PIK), and especially to Jonathan Donges and Norbert Marwan

The author is also thankful to the HOAPS group at MPI-M, UniHH and DWD for the provided HOAPS - GPCC datasets.

12

13

Irina.Petrova@zmaw.de