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Friday 15 December 2017

The Indian monsoon variability and civilization changes in the Indian subcontinent

Although while describing the periods and their relation with data , they strictly rely on the so called AIT/AMT time frame , the data apparently suggest that during early and mature phases monsoon was strong with warm and wet climate (the phase had climatic stability) and the  intensification happened around  ~4550 YBP, but slowly started to decline though remained considerably strong up to   ~3850 YBP). So the 4.2 ka BP event did not create a sudden impact in ancient India , they reckon start of drier and cooler conditions around ~4100 YBP, but from ~3850 YBP to ~3300YBP , the dry and cool conditions prevailed which coincides with de-urbanization,reduced river flows and eastward migration  . But  the period of ~3400–3050 yr BP according to them, was when conditions improved before getting bad around ~3100 YBP , they reckon after that there was intensification of rain again and after were some more dry periods around 600-500 BC with more dry and wet periods followed. They have tried to link each dry and wet phase, with some significant periods of India's history and pre-history. I must tell this approach can be quite  risky and confusing , though is interesting and innovative nevertheless. 

The Indian monsoon variability and civilization changes in the Indian subcontinent

Gayatri Kathayat,1 Hai Cheng,1,2* Ashish Sinha,3 Liang Yi,4 Xianglei Li,1 Haiwei Zhang,1
Hangying Li,1 Youfeng Ning,1 R. Lawrence Edwards2
The vast Indo-Gangetic Plain in South Asia has been home to some of the world’s oldest civilizations, whose fortunes ebbed and flowed with time—plausibly driven in part by shifts in the spatiotemporal patterns of the Indian summer monsoon rainfall. We use speleothem oxygen isotope records from North India to reconstruct the monsoon’s variability on socially relevant time scales, allowing us to examine the history of civilization changes in the context of varying hydroclimatic conditions over the past 5700 years. Our data suggest that significant shifts in monsoon rainfall have occurred in concert with changes in the Northern Hemisphere temperatures and the discharges of the Himalayan rivers. The close temporal relationship between these large-scale hydroclimatic changes and the intervals marking the significant sociopolitical developments of the Indus Valley and Vedic civilizations suggests a plausible role of climate change in shaping the important chapters of the history of human civilization in the Indian subcontinent.
Yog .

See also :
Holocene landscape dynamics in the Ghaggar-Hakra palaeochannel region at the northern edge of the Thar Desert, northwest India

Thursday 7 December 2017

Indus Administrative Technologies. New data and novel interpretations on the Indus stamp seals and their impressions on clay

Another fantastic research from Dennys Frenez . The presentation is quite beautiful, waiting eagerly for the proper paper .

Indus Administrative Technologies. New data and novel interpretations on the Indus stamp seals and their impressions on clay
This presentation summarizes the results of different studies that I conducted over the past ten years on Indus Civilization stamp seals and their impressions on clay (46th Annual Conference on South Asia, University of Wisconsin-Madison, 26–29 October 2017)

From the presentation :

 Clay sealing technology in the Indus Civilization
Same administrative sealing procedure reconstructed for the Middle East:
Clay sealings used to control and record the access to specific rooms and containers and to the goods they contained
Clay sealings used in the internal administration of the sites and not for securing the integrity of shipped packages
Clay sealings were used to control main types of containers used in the Middle East
Structures and closing devices unique of the Indus Civilization sites
About one/third of the clay sealings have been stamped with more than one seal
(sharing of ownership,storage space or administrative duties?)
Storage and administrative technologies and procedures were adapted to the socioeconomic organization of the different sites or part of the sites
Considering the lower occurrence of clay sealings at Indus sites respect to sites in the Middle East and the use of a different storage technology I think they were not equally used for the daily redistribution of food rations but to control goods and raw materials of pivotal socioeconomic and ideological importance in the Indus society

Yog .

Tuesday 5 December 2017

Holocene landscape dynamics in the Ghaggar-Hakra palaeochannel region at the northern edge of the Thar Desert, northwest India

Here is another important research on Sarasvati (Ghaggar-Hakra) . It seems to suggest that flow continued in post urban phases after major dry ups   , which is quite likely  as per the accounts of Indian tradition . Harsha  in 7th Century said to have  performed for example funeral rites of his father near the Sarasvati . Even today it exists , especially in monsoon season , Ghaggar in upper course (also in other periods) , using google maps you can see it stops only near Suratgarh.
Also the Sarsuti river, which is identified as the original upper course of Sarasvati, is still an ephemeral river.

Holocene landscape dynamics in the Ghaggar-Hakra palaeochannel region at the northern edge of the Thar Desert, northwest India
Julie A.Durcan a David S.G.Thomas a Sanjeev Gupta b Vikas Pawar c Ravindra N.Singh d Cameron A.Petrie e
Precession-forced change in insolation has driven de-intensification of the Asian Monsoon systems during the Holocene. Set against this backdrop of a weakening monsoon, Indus Civilisation populations occupied a number of urban settlements on the Ghaggar-Hakra plains during the mid-Holocene from 4.5 ka until they were abandoned by around 3.9 ka. Regional climatic variability has long been cited as a potential factor in the transformation of Indus society, however there remain substantial gaps in the chronological framework for regional climatic and environmental change at the northern margin of the Thar Desert. This makes establishing a link between climate, environment and society challenging. This paper presents 24 optically stimulated luminescence ages from a mixture of 11 fluvial and aeolian sedimentological sites on the Ghaggar-Hakra floodplain/interfluve, an area which was apparently densely populated during the Indus urban phase and subsequently. These ages identify fluvial deposition which mostly pre-dates 5 ka, although fluvial deposits are detected in the Ghaggar palaeochannel at 3.8 ka and 3.0 ka, post-dating the decline of urbanism. Aeolian accumulation phases occur around 9 ka, 6.5 ka, 2.8 ka and 1.7 ka. There is no clear link to a 4.2 ka abrupt climate event, nor is there a simple switch between dominant fluvial deposition and aeolian accumulation, and instead the OSL ages reported present a view of a highly dynamic geomorphic system during the Holocene. The decline of Indus urbanism was not spatially or temporally instantaneous, and this paper suggests that the same can be said for the geomorphic response of the northern Thar to regional climate change.
Indus Civilisation Fluvial Aeolian OSL dating Palaeo environment Drylands Northern Thar Desert

From the paper :

 6. Conclusion 
This study presents OSL ages for Holocene fluvial and aeolian activity in the Ghaggar-Hakra inter fluve on the northern margin of the Thar Desert. This chronology shows fluvial deposition in the currently visible palaeochannel during the early Holocene from 8.5ka until ~3 ka. More intensive fluvial processes are inferred prior to 5 ka, when thicker fluvial units are deposited. After 3 ka, sediments in the Ghaggar-Hakra channel adjacent to the Indus Civilisation urban site of Kalibangan fine significantly, and slightly further to the west, sediment dated to 3 ka are capped by a silty unit of 0.75 m.This may suggest a weakening of fluvial activity post 3 ka and possibly ephemeral overbank flooding in this area at least. These findings complement other studies in the Ghaggar-Hakra system(e.g. Saini et al., 2009; Saini and Mujtaba, 2010) and are consistentwith regional palaeo hydrological records (e.g. Dixit et al., 2014a,2014b). Like the fluvial sedimentation, aeolian accumulation is recorded across the Holocene, with a period of enhanced accumulation at around 9 ka identified, as well as two ranges of ages at around ~7.1-5.7 ka and later between ~2-1.7 ka. These ages are consistent with regional records of aeolian accumulation in Ghaggar-Hakra region (e.g. Shitaoka et al., 2012) and more broad lyin the Thar Desert (e.g. Kar et al., 1998; Thomas et al., 1999; Singhviand Kar, 2004). In this study we demonstrate phases of fluvial ac-tivity and aeolian accumulation coincide, which should be considered as normal behaviour in a dry land context (Thomas,2013).This evidence adds to the emerging picture of the Holocene Ghaggar-Hakra as a low energy fluvial system broadly driven by regional changes in the monsoon, however, this response appearsto be neither simple nor linear. Thicker units of fluvial sediment are deposited in the early Holocene, although in the sediments sampled, there is no statistically significant change in particle size which can be used to infer a weakening of fluvial transport energies with time. Thinner fluvial units accumulated during the mid-Holocene and the presence of fine sediments, predominantly silts,in the channel close to the Indus Civilisation urban site Kalibangan after 3 ka may represent a phase of weakened fluvial activity.Coeval fluvial and aeolian accumulation provides a view of oscil-lating phases of relative humidity and aridity throughout the Holocene, resulting in the accumulation of dune sediments on the Ghaggar-Hakra inter fluve. Further research considering the geomorphic and environmental response to climatic fluctuation across the full extent of the Ghaggar-Hakra interfluve, which will further improve our understanding of changing environmental conditions under fluctuating monsoon regimes, as well as in form the response of past civilisations to climatic and environmental variability. 

Yog (Science Direct) .

See also :
Counter-intuitive influence of Himalayan river morphodynamics on Indus Civilisation urban settlements

The Chronology of Puranic Kings and Rigvedic Rishis in Comparison with the Phases of the Sindhu–Sarasvati Civilization

Early users of monsoon winds for navigation

Not on something new but a nice article from Current Science .

Early users of monsoon winds for navigation
Sila Tripati
The maritime history of India can be traced back to the Harappan Civilization. Studies suggest that even at that time, monsoon winds and currents assisted in navigation. Recent archaeological exploration and excavations along the Indian margin, Persian Gulf, Red Sea, and coasts of Southeast Asia provide convincing evidence about a maritime network and connections between mariners of India and other parts of the world in ancient times. The author of Periplus of the Erythraean Sea (PES) (60–100 CE) has credited Hippalus (~45 CE), the Greek mariner, with the discovery of monsoon winds and the mid-ocean route to the Indian ports from the Mediterranean. However, archaeological findings of Harappan Civilization, as well as the Vedic and Sangam period texts, suggest that the mariners of India who were trading in the Indian Ocean and adjoining seas had knowledge about monsoon winds much before Hippalus. In this paper, an attempt has been made to demonstrate the fact that knowledge of the monsoon winds was familiar to Indian mariners during the Harappan Civilization as well as in the later period.

 Figure 1. Figure showing the sites mentioned in the text.

 Figure 3 a, b. A seal and a terracotta
amulet from Mohenjo–Daro depict ship
with cabin and birds.

Figures like above  from Mohenjo Daro reminds passages from Rig Veda , like for example RV  I.25.7 about Varuna :
vedā yo vīnāṃ padamantarikṣeṇa patatām | veda nāvaḥ samudriyaḥ|| 
 "He knows the path of birds that fly through heaven, and, Sovran of the sea,He knows the ships that are thereon." (Griffith) 
 "He who knows the track of birds flying through the midspace, knows the (courses of the) boats, since he belongs to the sea." (Jamison-Brereton)
Or  in the old 7th book there is a clear reference to sea travel RV 7.88.3:

ā yad ruhāva varuṇaśca nāvaṃ pra yat samudram īrayāva madhyam| 
"When Varuṇa and I embark together and urge our boat into the midst of ocean" (Griffith)
''When we two, Varuṇa and (I), will board the boat, when we two will raise the middle of the sea ''(Jamison-Brereton)
There are some interesting remarks from Wikipedia on Samudra also :
Samudra and ships[edit]
Some scholars like B.R. Sharma hold that the Rigvedic people may have been shipbuilders engaging in maritime trade.[9] In Rigveda 1.25.7; 7.88.3 and other instances, Samudra is mentioned together with ships. In RV 7.89.4 the rishi Vasishta is thirsting in the midst of water. Other verses mention oceanic waves (RV 4.58.1,11; 7.88.3). Some words that are used for ships are Nau, Peru, Dhi and Druma. A ship with a hundred oars is mentioned in RV 1.116. There were also ships with three masts or with ten oars.[10] RV 9.33.6 says: 'From every side, O Soma, for our profit, pour thou forth four seas filled with a thousand-fold riches."

On Rig Veda, the papers suggestion is quite familiar, with an interesting interpretation on Maruts :

Rig Veda and monsoon winds
Though there are diverse opinions on the
Rig Veda (Rg Veda) (1700 and 1100 BCE)
and its period, it is believed that Rig
Veda is the oldest literary work of the
Indian subcontinent. There are several
hymns that have referred to the wind,
waves, tides, water, thunder and rain,
rivers, sea, etc.4,36,37. Similarly, many
verses praise Parjanya (the thunder and
rain), which shows that the Rig Vedic
people were aware of the rainy season
which comes in a certain period every
year3. Monsoon winds are termed as maruts
in the Rig Veda, whereas in the later
Vedic texts, monsoon was referred to as
salila vada (sahla vada) (the wind from
the ocean, especially SW monsoon)38
the Buddhist texts mentioned kalamegha
(dark clouds) and varshavalshaga (heavy
rains)5,39. Despite the available information
on monsoon, rain, and wind in the
Rig Veda, the following questions were
often asked: was the sea known to the
Rig Vedic people? Were the Rig Vedic
people familiar with seafaring? Numerous
statements can be found in the Rig
Veda concerning Samudra for sea
, Nau,
Nava, Ratha being the general terms for
boat or ship and Navya for navigation or
sailor38. Among all these types of water
crafts, nau was the sea vessel in which
oars, sails, masts and anchors were carried.
During favourable wind, sails were
used so that naus could float and move
with speed
Yog .

It is by no means surprising, that the people of Rig Veda ,with a robust possibility knew about ocean and seafaring . The Sindhu-Sarasvati Civilization, shows strong material and cultural continuity, from Neolithic to Iron ages and even today !. Rig Veda is of course an integral part of that continuity.