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| Time periods (yr BP) calibrated dates | Western Arabian Sea records (SWM wind records) ([10, 16–20] & references therein) | Southeastern Arabian Sea records (SWM precipitation records) [21–28] | Speleothems records from India [1, 29–31] | Speleothem recordsfrom Oman [32–34] | Bay of Bengal records [35–39] | Northern Arabian Sea [40–46] | World climatic records [17, 47, 48] |
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| 21000 to 15000 | Weakest SWM at Last Glacial Maximum (~21 kyr BP); weak SWM during later stages of last glacial period | High δ 18O value of Gs. ruber, low productivity, that is, low Corg and high Pteropods abundance suggests low runoff into eastern Arabian Sea indicating reduced monsoon. | No record available | | Weak SW monsoon, suggested by high δ 18O of Gs. sacculifer and Gs. ruber and minimum fluvial discharge observed by the high Chlorite/Illite ratio, low Kaolinite abundance. | Weak SWM based on low TOC values with minimum at ~16 kyr BP matching with Heinrich event 1. | Part of last glacial period, Synchronous with Greenland aridity |
| 15000 to 11700 | SWM strengthening commences; weaker monsoon during colder episodes such as Younger Dryas | SWM precipitation starts increasing with weaker/stronger monsoon during cooler/warmer episodes | δ 18O in speleothem from Timta cave, western Himalaya show fluctuating monsoon with lesser precipitation during cooler periods | No Speleothem record available | Increasingly stronger SWM suggested by low δ 18O of foraminifer; weaker/stronger monsoon during cooler/warmer episodes | Fluctuating monsoon inferred; weaker monsoon during cooler periods such as Younger Dryas | Deglaciation period, Synchronous with European Bolling-Allerod warm event, also coeval with melt water Pulse IA. |
| 11700 to 10200 | SW monsoon still weak as deciphered from multiple proxies | High δ 18O value of Gs. ruber, low Corg and high Pteropods abundance suggest low runoff | No Speleothem record available | | δ 18O of Gs. sacculifer and Gs. ruber reduced fluvial fluxsuggested by the high C/I ratio, low Kaolinite abundance suggested the Weak SWM | Increasing monsoon observed during this period; early Holocene Monsoon maxima observed; δ 18O record don’t show a clear-cut early Holocene monsoon maxima | End of Younger Dryas & beginning of Holocene |
| 10200 to 9800 | Multiple proxiessuggest strong SWM early Holocene monsoon maxima | δ 18O value foraminifera do not show a clear-cut early Holocene monsoon maxima but suggest a slightly increasing trend during that period | Low δ 18O value of the speleothem suggests high rainfall | δ 18O value of warm mixed dweller planktic foraminifera do not show a clear-cut early Holocene monsoon maxima but suggest a slightly increasing trend during that period similar to Eastern AS records | Early Holocene monsoon maxima matches with warm north Atlantic climate (low haematite in sediment cores) |
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| 9800–8800 | SWM weakened after early Holocene monsoon maxima | δ 18O value of Gs. ruber suggest low runoff | No Speleothem record available | Positive excursion in the value of δ 18O of stalagmite suggests arid climate | Decreasing trend in the value of δ 18O of Gs. sacculifer and Gs. ruber suggest higher runoff | From early to mid-Holocene, the Total Organic Carbon values in the core 111KL stays more or less uniform indicating unvarying monsoon, while the δ 18O from nearby cores either stay unvarying or display a negative excursion indicating strengthening monsoon | Very high percentage of hematite from N. Atlantic suggests cool period |
| 8800–5400 | Up to mid-Holocene, SWM was strong based on multiple proxies although % Gs. bulloides exhibit a declining trend | low δ 18O value of Gr. menardii reported and suggesting high rainfall | No Speleothem record available | Increasing value of δ 18O of stalagmite suggest increasingly arid climate at the Oman Site | Maximum fluvial discharge suggested by low δ 18O and strong SW monsoon. | Low percentage of hematite from N. Atlantic suggests warm period; temperature reconstruction from Greenland Ice cores (GISP2) suggest warm climate; 8.2 kyr cool event from GISP2 is not reflected in monsoon reduction |
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| 5400–2900 | During Mid-Holocene to early part of late Holocene, multiple studies show slightly increasing monsoon but a few also observed a decline (e.g., % Gs. bulloides) | High rain fall suggested by the lower value of δ 18O Gs. sacculifer and Gs. ruber | No Speleothem record availablefrom India | Increasing trend in δ 18O value was observed in the Oman stalagmite suggesting decreasing SWM | High water discharged by G-B river suggested by lower values of δ 18O Gs. ruber. More negative values of δ 18O of Gs. sacculifer and Gs. ruber suggest the higher runoff | After mid-Holocene, the TOC values decreases of Gs. ruber indicating declining monsoon while proxies like δ 18O, Ba/Al suggest an unvarying or strengthening monsoon | Low percentage of hematite at N. Atlantic suggests the humid, warm climate; GISP2 suggests continuous, unvarying warmth |
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| 2900–2100 | Declining SWM deciphered from several studies | Positive δ 18O values of Gs. ruber suggest low runoff. | High-resolution speleothem records available from India; declining SWM suggested by increasingly positive δ 18O of Gupteswar and Sota speleothem records | No growth of Oman Stalagmite | High Chlorite content and δ 18O higher value suggest the arid climate | High runoff from Indus river suggested by thicker varve sediment layer | GISP2 temperature records suggest unvarying northern hemisphere, high-latitude warmth |
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| 2100–1900 | A period of widespread aridity is reported from varied regions & proxies such as δ 18O of foraminifera, abundance (~5%) of Globigerina bulloides and reduction in dinoflagellate population in the west Arabian sea suggesting weak upwelling, weak SWM | Positive δ 18O values of foraminifera suggest low freshwater run-off indicating severely weakened SWM precipitation. | Extremely low rain fall recorded from Gupteswar stalactite, suggested by the prominent positive excursion in δ 18O values | No growth of Oman Stalagmite | Low Chlorite ratio, high Kaolinite ratio and depletion in δ 18O of Gs. ruber suggests the arid climate andreduced water discharge in to BOB | Positive values of δ 18O & reduced varve thickness indicate reduced Indus river discharge | Low percentage of hematite at N. Atlantic suggests humid, warm climate |
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| 1900–1600 | Slightly strengthening monsoon but overall the monsoon is on weaker side | δ 18O records of Gs. ruber and Gs. sacculifer suggest increasing SWM | Lower δ 18O record from both Gupteswar & Sota caves suggest increasing trend of rainfall. | No growth of Oman Stalagmite | Slight positive excursion observed in the foraminiferal δ 18O values indicating declining monsoon | An increase in the thickness of varve sediment suggests the higher water discharge from Indus | Higher hematite content suggest cold climate in N. Atlantic |
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| 1500–1400 | Very low abundance of Globigerina bulloides (5%) suggests extreme reduction in upwelling and wind strength | Higher value of δ 18O records of Gs. ruber and Gs. sacculifer suggest weakening of SWM | High δ 18O of Gupteswar stalactite, Orissa suggests the weak monsoonal run-off | No growth of Oman Stalagmite | Slightly declining trend in δ 18O values of foraminifera indicate strengthening monsoon | An increase in the thickness of varved sediments suggests higher water discharge from Indus | Low value of Hematite percentage at North Atlantic (Medieval warm period) |
| 1400–1200 | Multiple proxies suggest increasing monsoon during this period | A clear-cut decreasing trend in foraminiferal δ 18O values indicate strengthening monsoon | Depletion in δ 18O shows increasing trend of rainfall recorded at Gupteswar and Dandak caves. | High precipitation indicated by Oman stalagmite depleted δ 18O record |
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| 1200–1000 | Low Gg. bulloides abundance & other proxies suggest significantly weak upwelling due to weakened SWM | An arid event centered at ~1100 yr BP reflected by the sudden decline in δ 18O of Gs. ruber and Gs. sacculifer | Low rain fall recorded at Gupteswar and Dandak caves | Higher δ 18O values suggest arid conditions |
After a slight peak, the δ 18O exhibit positive excursion indicating reduced SWM strength | Lower varve thickness and high δ 18O of Gs. ruber suggests weak SWM (63 KA) | Low value of Hematite percentage at North Atlantic (Medieval warm period) |
| 1000–800 | Very low abundance of Globigerina bulloides suggests the weak SWM | Increase in δ 18O records Gs. ruber and Gs. sacculifer of due to increase in salinity of east Arabian Sea suggests major event of aridity centered at ~850 yr BP | Aridity observed at Dandak caves indication reduced precipitation | Oman stalagmite records the increase in δ 18O which suggest an arid condition | Lower Varve thickness and sharp increase in δ 18O of Gs. ruber suggests the weak SWM |
| 800–500 | Decreasing trend of Gg. bulloides abundance suggests weak SWM | Low runoff, reduced precipitation event centered at ~500 yr BP suggested by increase in δ 18O of Gs. ruber and Gs. sacculifer | Depletion in δ 18O shows increasing trend of rainfall recorded in Gupteswar & Dandak speleothem | Negative excursion in speleothem δ 18O values indicate strengthened precipitation | Lower varve thickness suggests weak monsoon strength | Increasing trend in the % of hematite at N.Atlantic suggests the cool climate |
| 500–400 | High abundance of Gg. bulloides suggests strong SWM | Increase in the δ 18O records of Gs. ruber and Gs. sacculifer suggest weak SWM | Reduced precipitation suggested by increase in δ 18O speleothems record | Reduced precipitation suggested by increase in δ 18O record in Oman stalagmite | Lower Varve thickness and high δ 18O of Gs. ruber suggests weak SWM | Synchronous with little Ice Age, cooling at Bermuda rise and brief increase in hematite percentage |
| 400–300 | Very low abundance of Globigerina bulloides suggests weak SWM |
SWM shows an increasing trend | High rain fall inferred from Dandak, and Gupteswar caves |
No growth of Oman Stalagmite | Ganges-Brahmaputra river discharge shows a declining trend |
High varve thickness off Karachi and low δ 18O of Gs. ruber suggest strong SWM |
| 300–100 | High abundance of Gg. bulloides suggests the strong SWM | Rain fall increased as seen in from Dandak Gupteswar Sota and Akalagavi caves, the lower δ 18O record suggests higher runoff | Low value of Hematite percentage at North Atlantic indicating warm, humid climate |
| 50–Present | High abundance of Gg. bulloides suggest strong SWM | Very low rain fall was recorded from Dandak and Akalagavi caves |
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