Prasad et al. (2025) The differential impact of global temperature trends on prolonged droughts in the Indian Monsoon realm during the past five millennia

Identification

• Journal: Global and Planetary Change
• Year: 2025
• Date: 2025-11-22
• Authors: Sushma Prasad, Praveen K. Mishra, Martina Stebich, Sylvia Pinkerneil, Salman Khan, Priya Pattancheri, Arshid Jehangir, Ambili Anoop, Torsten Utescher, R. Krishnan, Amzad H. Laskar, Birgit Gaye
• DOI: 10.1016/j.gloplacha.2025.105197

Research Groups

• Institute for Geosciences, Potsdam University, Germany
• Department of Geology, School of Sciences, Cluster University of Jammu, India
• Senckenberg Research Station of Quaternary Palaeontology, Weimar, Germany
• GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
• Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
• Department of Environmental Science, University of Kashmir, Srinagar, India
• Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research (IISER) Mohali, India
• Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat, India
• Universität Hamburg, Institute for Geology, Hamburg, Germany

Short Summary

This study provides a comprehensive hydroclimate overview of the past 5 millennia in the Indian Summer Monsoon realm (ISMr) by integrating existing records with new data from Manasbal Lake. It identifies two major reorganizations of seasonal precipitation pathways linked to high-latitude and tropical temperature trends, which triggered asynchronous prolonged droughts across the ISMr.

Objective

• To reconstruct a high-resolution record of late Holocene Indian Summer Monsoon (ISM)-westerlies interaction from the NW Himalaya using a multi-proxy approach on lake sediments, focusing on extreme hydroclimatic events.
• To identify spatiotemporal variability of precipitation seasonality and prolonged droughts (PDs) over the ISMr.
• To compare regional PDs with latitudinal temperature shifts and examine how tropical and extratropical teleconnections altered seasonal precipitation pathways to trigger centennial palaeodroughts in the ISMr.

Study Configuration

• Spatial Scale: Indian Summer Monsoon realm (ISMr), with a focus on Manasbal Lake in the NW Himalaya, and comparative analysis with sites in the core monsoon zone (CMZ) and other regions of the Indian subcontinent.
• Temporal Scale: Past 5 calendar millennia (5000 years before present).

Methodology and Data

• Models used:
  • P_Sequence method from OxCal for radiocarbon age modeling.
  • Principal Component Analysis (PCA) in SRPlot for pollen data.
  • Simple isotopic model developed to resolve relative contributions of westerlies versus ISM.
• Data sources:
  • New data from Manasbal Lake sediment cores:
    • Accelerator Mass Spectrometry (AMS) 14C dating of organic matter.
    • μ-XRF scanning for elemental composition (e.g., Ti, Al, K, Ca/Ti, S/Ti).
    • X-ray diffraction (XRD) for mineral concentration (e.g., calcite, pyrite, gypsum, halite).
    • Stable isotope analysis (δ13Ccarb, δ18Ocarb) of bulk carbonate samples.
    • Total Organic Carbon (TOC) analysis.
    • Grain-size distribution analysis.
    • Palynological investigations (pollen, spores, non-pollen palynomorphs).
  • Existing hydroclimate records: High-resolution, chronologically constrained continental archives from various ISMr sites (e.g., Lonar Lake, Rara Lake, Nal Lake, Pariyaj Lake, Khajjar Lake, Benital Lake, Kotla Dahar, Thar Desert Lakes, Shantisagar Lake, Ennamangalam Lake, Twintaung Lake, Chopta Valley core, Arabian Sea core, Lake Maharlu, Dead Sea, Alpine lakes).
  • Reconstructed climate drivers: Solar irradiance, high-latitude Northern Hemisphere and tropical temperature anomalies, ITCZ variability, ENSO reconstructions, Pacific Decadal Oscillation (PDO) Index, North Atlantic cooling.
  • Modern climate data: δ18O of modern precipitation, inflow, groundwater, and lake waters for proxy calibration and interpretation.

Main Results

• Two major reorganizations of seasonal precipitation pathways were identified around 5 calendar millennia and 1.2 calendar millennia, linked to shifts in high-latitude and tropical temperatures.
• These reorganizations triggered asynchronous prolonged droughts (PDs) across the ISMr:
  • NW Himalaya (Manasbal Lake) experienced a prolonged winter and summer drought from 3.9 to 2.9 calendar millennia.
  • The core monsoon zone (CMZ) experienced PDs from 4.6 to 3.9 calendar millennia and from 1.2 to 0.6 calendar millennia.
• The first reorganization (~5 calendar millennia) coincided with simultaneous cooling in high-latitude and tropical regions, leading to a southward shift of winter westerlies (causing winter droughts in NW Himalaya from 5 to 2.9 calendar millennia) and a northward-shifted ISM (causing PD in the CMZ from 4.6 to 3.9 calendar millennia).
• Within the 5–2.9 calendar millennia interval, diminishing east–west ISM rainfall (3.9–2.9 calendar millennia) and reduced winter precipitation culminated in a severe PD in Manasbal Lake, potentially reflecting a response to a positive phase of the Pacific Decadal Oscillation (PDO).
• The second reorganization (~1.2 calendar millennia) coincided with divergent temperature trends (cooling in the high-latitude Northern Hemisphere and warming in the tropics) and increased El Niño Southern Oscillation (ENSO) activity, causing the second PD in the CMZ (1.2–0.6 calendar millennia).
• During the second CMZ drought, wetter conditions in southern India were observed, linked to cyclonic disturbances formed due to warmer sea surface temperatures (SST) over the Bay of Bengal during El Niño conditions.

Contributions

• Presents the first high-resolution multiproxy palaeoclimate record from Manasbal Lake (NW Himalaya), elucidating the significant impact of ISM and westerly precipitation on regional hydroclimate over the past 5 calendar millennia.
• Provides a comprehensive characterization of the spatiotemporal variability and asynchronicity of prolonged droughts across the Indian Summer Monsoon realm.
• Establishes a link between these prolonged droughts and two major reorganizations of precipitation pathways, driven by shifts in high-latitude and tropical temperature trends.
• Highlights the critical importance of considering the complexities of regional temperature trends in refining predictive climate models for the Indian Monsoon realm.
• Developed a novel isotopic model to distinguish the relative contributions of westerlies versus ISM to past hydrological changes.

Funding

• German Research Foundation (FOR 1380) within the framework of the HIMPAC (Himalaya: Modern and Past Climates, FOR 1380) project (Projects #155487509, 495241454, and TREX #495241454 to S. Prasad; DFG project STE 1665/8-1 to M. Stebich).

Citation

@article{Prasad2025differential,
  author = {Prasad, Sushma and Mishra, Praveen K. and Stebich, Martina and Pinkerneil, Sylvia and Khan, Salman and Pattancheri, Priya and Jehangir, Arshid and Anoop, Ambili and Utescher, Torsten and Krishnan, R. and Laskar, Amzad H. and Gaye, Birgit},
  title = {The differential impact of global temperature trends on prolonged droughts in the Indian Monsoon realm during the past five millennia},
  journal = {Global and Planetary Change},
  year = {2025},
  doi = {10.1016/j.gloplacha.2025.105197},
  url = {https://doi.org/10.1016/j.gloplacha.2025.105197}
}