Paper: Abhik Sintra et al 2019

Title: A brief history of Asian summer monsoon evolution in the Cenozoic era

For a fuller description of the paper itself, go to the end of this web page.

Each simulation published in this paper corresponds to a unique 5 or 6 character code on the web pages.
The following table lists the name of the simulation as used in the paper, and the corresponding code name

The webpage gives you the ability to examine the published simulations, but you can also download the raw (netcdf) files to perform your own analysis. Detailed instructions on how to use the webpages and access the data can be found here: Using_BRIDGE_webpages.pdf

A series of palaeoclimate model experiments and sensitivity studies for each geologic stage over for the last 66 million years using HadCM3L. Each experiments uses the Getech palaeogeography and time specific boundary conditions. See individual experiments for details. alt geography refers to alternative geography for Asia based on latest evidence.

You can have make you own analysis and plots by going here

Simulation Name as in PaperSimulation name on web pages
DaniantfgsN
SelandiantfgsO
Thanetiantdwjc
YpresiantfgsQ
LutetiantfgsR
BartoniantfgsS
PriaboniantfgsT
RupeliantfgsU
ChattiantfgsV
AquitaniantfgsW
BurdigaliantfgsX
LanghiantfgsY
SerrevalliantfgsZ
TortoniantfgSa
MessiniantfgSb
ZancleantfgSc
PiacenziantfgSd
GelasiantfgSe
Pre-industrialtdezc1
Lutetian-alt geographytflzR
Bartonian-alt geographytflzS
Priabonian-alt geographytflzT
Rupelian-alt geographytflzU
Chattian-alt geographytflzV
Aquitanian-alt geographytflzW
Burdigalian-alt geographytflzX
Langhian-alt geographytflzY


This is a fuller description of paper

How did the Asian monsoon evolve over the last 66 million years?

NameAbhik et alb
Brief DescriptionHow did the Asian monsoon evolve over the last 66 million years?
Full Author ListS. Abhik, F. Capitanio, B.N. Goswami, A. Farnsworth, P. Clift, D. Dommenget
TitleA brief history of Asian summer monsoon evolution in the Cenozoic era
Year2026
Journalnpj Climate and Atmospheric Science
Volume9
Issue
Pages
DOI10.1038/s41612-025-01259-7
Contact's NameAlex Farnsworth
Contact's emailalex.farnsworth@bristol.ac.uk
AbstractThe evolution of the Asian Summer Monsoon (ASM) over geological timescale remains uncertain despite its fundamental role in shaping regional climate ecosystems and civilizations. Using a series of time-slice simulations with a paleo-climate model, we assess how India-Eurasia collision tectonics Tibetan Plateau (TP) uplift, and atmospheric CO2 variability influenced ASM evolution through the Cenozoic. Our simulation-based results suggest that ASM intensification was contingent on the TP exceeding an areal mean elevation of ~ 3.5 km in the late Eocene-Oligocene (27-38 million years ago, Ma), which strengthened the upper-tropospheric temperature gradient, promoted the seasonal northward shift of the Intertropical Convergence Zone (ITCZ), and restructured atmospheric circulation. Initially confined to East Asia, monsoonal rainfall expanded across South Asia by the Oligocene, coinciding with enhanced circulation and reversing the meridional relative sea surface temperature gradient in the Neotethys. While TP uplift played the primary role in early ASM evolution, declining atmospheric CO2 levels became increasingly influential after the late Miocene. These findings, supported by sedimentary records of weathering and erosion, underscore the dominant role of TP in climate-tectonic interactions and ASM evolution over geological timescales.