The issue was subjected to a scrutiny in later years. It has now been found that the three studies as discussed do not give clinching evidence in support of the view that there indeed has been a marked climatic shift in the region since the days of Indus civilisation. Irfan Habib asserts that the climatic – shift view is “inconsistent with the drainage system at Mohenjodaro and Kalibangan which could not have withstood any heavier rainfall than what the area now receives.
If an ‘arid’ phase really followed a ‘wet’ phase in the present geological age (Holocene), then the change must have long preceded the Indus civilisation”. Similarly, for Gurdip Singh’s study Possehl writes: “The changing salinity of these lakes, which appears to be well documented, need not be attributed to changes in rainfall. The geology of Rajashan is complex. The three lakes investigated are hyper saline today, but there are also fresh water lakes in this same region (Lakes Pushkar and Ganger).
This observation leads to the conclusion that under one climatic regime in Rajasthan, there can be both fresh water and hyper saline lakes, calling into question the Singh hypothesis”. It can now be safely contended that on the whole there has been no significant shift in climate in the Indus area.
The region has remained semi-arid since the beginning of the Indus Civilisation with inadequate rainfall so as not to support agriculture without the assistance of supplementary irrigation. The flood-plain agriculture of the Indus civilisation was characteristic of the climatic conditions and the peculiar behaviour of seasonal floods in the rivers.