Journal cover Journal topic
Earth System Dynamics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 4.351 IF 4.351
  • IF 5-year value: 5.124 IF 5-year
    5.124
  • CiteScore value: 4.44 CiteScore
    4.44
  • SNIP value: 1.250 SNIP 1.250
  • IPP value: 4.10 IPP 4.10
  • SJR value: 2.203 SJR 2.203
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 29 Scimago H
    index 29
  • h5-index value: 31 h5-index 31
Discussion papers
https://doi.org/10.5194/esd-2019-42
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esd-2019-42
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: research article 05 Aug 2019

Submitted as: research article | 05 Aug 2019

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Earth System Dynamics (ESD).

Tropical and mid-latitude teleconnections interacting with the Indian summer monsoon rainfall: A Theory-Guided Causal Effect Network approach

Giorgia Di Capua1,2, Marlene Kretschmer1, Reik V. Donner1,3, Bart van den Hurk2,4, Ramesh Vellore5, Raghavan Krishnan5, and Dim Coumou1,2 Giorgia Di Capua et al.
  • 1Potsdam Institute for Climate Impact Research, Potsdam, Germany
  • 2VU University of Amsterdam, Institute for Environmental Studies, Amsterdam, Netherlands
  • 3Magdeburg-Stendal University of Applied Sciences, Magdeburg, Germany
  • 4Deltares, Delft, Netherlands
  • 5Indian Institute for Tropical Meteorology, Pune, India

Abstract. The alternation of active and break phases in the Indian summer monsoon (ISM) rainfall at sub-seasonal timescales characterizes each ISM season. Tropical and mid-latitude drivers influence this sub-seasonal ISM variability. The circumglobal teleconnection observed in boreal summer drives sub-seasonal variability across the mid-latitudes and a two-way interaction between ISM and the circumglobal teleconnection pattern has been hypothesized. We use causal discovery algorithms to test the ISM-circumglobal teleconnection hypothesis in a causal framework. Our analysis shows a robust causal link from the circumglobal teleconnection pattern and the North Atlantic region to ISM rainfall. We estimate the normalized causal effect (CE) of this link to be about 0.2 (a one standard deviation shift in the circumglobal teleconnection causes a 0.2 standard deviation shift in the ISM rainfall one week later). In turn, the ISM rainfall influences back the circumglobal teleconnection pattern, however weakly. Moreover, we identify causal links that represent the internal dynamics of the ISM convective cell at weekly timescales: Periods with strong updraft lead to strong rainfall one week later, but the resulting increase in static stability suppresses convection again. In our analyses, this internal ISM dynamics has the strongest CE of 0.5. Tropical Madden-Julian Oscillation variability has a CE of 0.2–0.3. Our results show that the most of the ISM variability on weekly timescales is due to internal dynamics of convective cell, but both tropical and mid-latitude teleconnections have a substantial influence. Identifying these local and remote drivers paves the way for improved sub-seasonal forecasts.

Giorgia Di Capua et al.
Interactive discussion
Status: open (until 16 Sep 2019)
Status: open (until 16 Sep 2019)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Giorgia Di Capua et al.
Giorgia Di Capua et al.
Viewed  
Total article views: 144 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
117 24 3 144 7 1 2
  • HTML: 117
  • PDF: 24
  • XML: 3
  • Total: 144
  • Supplement: 7
  • BibTeX: 1
  • EndNote: 2
Views and downloads (calculated since 05 Aug 2019)
Cumulative views and downloads (calculated since 05 Aug 2019)
Viewed (geographical distribution)  
Total article views: 91 (including HTML, PDF, and XML) Thereof 90 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 19 Aug 2019
Publications Copernicus
Download
Short summary
Both drivers from the mid-latitudes and from the tropical regions have been proposed to influence the Indian summer monsoon (ISM) subseasonal variability. To understand the relative importance of tropical and mid-latitude drivers, we apply recently developed causal discovery techniques to disentangle the causal relationships among these processes. Our results show that there is indeed a two-way interaction between the mid-latitude circulation and ISM rainfall over central India.
Both drivers from the mid-latitudes and from the tropical regions have been proposed to...
Citation