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Mahanta, Chandan
- A Novel Approach to Calculate Braiding of a Large Alluvial River
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Authors
Affiliations
1 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, IN
2 Department of Environmental Science, Tezpur University, Tezpur 784 028, IN
1 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, IN
2 Department of Environmental Science, Tezpur University, Tezpur 784 028, IN
Source
Current Science, Vol 115, No 6 (2018), Pagination: 1179-1185Abstract
Braiding pattern in sixteen reaches of the Brahmaputra river in Assam, India is discussed. A new braiding index has been introduced incorporating a fraction of area covered by sandbars, number of midchannel bars and maximum width of alluvial reach. Braiding parameters calculated using different formulae showed similar trend but higher values in 2014 compared to 1973. Increase of braiding in different reaches in 2014 was due to development of more sandbars and distributaries. The new index has shown comparable result with other approaches and better correlation with sinuosity.Keywords
Alluvial River, Braiding, Sandbars, Brahmaputra.Full Text
References
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- Dynamics of air–sea carbon dioxide fluxes and their trends in the global context
Abstract Views :164 |
PDF Views:77
Authors
Affiliations
1 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, IN
2 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039,, IN
3 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, IN
1 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, IN
2 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039,, IN
3 Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, IN
Source
Current Science, Vol 121, No 5 (2021), Pagination: 626-640Abstract
This article reviews the dynamics of CO2 fluxes in the global scenario. Most of the available techniques for sea-surface CO2 partial-pressure estimation are regional models that depend on the key regulating parameters of partial pressures. Global-scenario of fluxes reveals a contrasting trend, indicating subpolar- and polar-waters dominated by physical forcings in winter, releasing CO2 whereas a biological drawdown of atmospheric CO2 in summer. In the tropical oceans, thermal-regulation weakens biological forcing leading to influx in winter and outflux in summer. The Atlantic Ocean acts as an intense sink (–815 to –1295 mmol Cm–2 yr–1); the strong source in the Pacific-equatorial belt is balanced by temperate sinks. The Indian Ocean as a whole acts as a sink (–8.41 × 1015 mmol C yr–1) whereas the northwestern sub-basin acts as a source (2.04 × 1015 mmol C yr–1). The net global ocean uptake is 50 × 1015 mmol C yr–1 where the physical- and biological-forcings along with seasonality play crucial roles in the flux directionKeywords
Carbon dioxide fluxes, earth system, global scenario, ocean–atmosphere interface, seasonal variabilityFull Text
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