Current Science

Open Access Open Access  Restricted Access Subscription Access

Role of Meteorology and Local Orography on a Flood Event in the Lower Subansiri Basin and Post-Flood Changes to Land Use and Land Cover


Affiliations
1 School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Arugul, Jatni 752 050, India
2 Department of Geological Sciences, Gauhati University, Jalukbari 781 014, India
 

Extreme rainfall in the Arunachal Himalaya has the potential to create floods in the downstream regions of Assam, with the rivers in the region exceeding their capacity and competence. High-intensity rainfall also leads to higher sediment generation in the sub- Himalayan catchment. Though floods have been incurring huge losses to both life and property frequently in Assam, there are only a few studies on the meteorological and orographic dynamics of such extreme rainfall events and their potential to create a flood. The present study highlights the pre-flood and post-flood scenario in the Lower Subansiri Basin (LSB) in Brahmaputra valley, Assam, through satellite data analysis and ground field surveys to establish linkages between extreme rainfall events and a subsequent major flood event that occurred during September 2012. We observed that the flood was mostly triggered by the extreme rainfall induced by orographic lifting of moisture-laden winds from the south. In addition to submerging an area of ~1900 km2, the flood also brought along fragile Neogene clastics that increased barren soil over the floodplains by ~47% compared to the pre-flood period, thus disrupting the agrarian economy of the region for several cropping seasons. These findings demonstrate the need for a reliable meteorological forecast for extreme rainfall as a prerequisite for developing effective flood-forecasting models in the Brahmaputra valley, which will positively contribute towards flood hazard management in the region.

Keywords

Extreme Rainfall, Flood, Meteorology, Orography, Sand Aggradation.
User
Notifications
Font Size

  • WMO, Annual Report, World Meteorological Organization, Geneva, Switzerland, 1994.

  • WMO, Atlas of Mortality and Economic Losses from Weather, Climate and Water Extremes, WMO No. 1123, World Meteorological Organization, Geneva, Switzerland, 2014.

  • Das, R. K., Census of India 2011: Provisional Population Totals – Assam, Series 19, Paper 1, 2011.

  • Dhar, O. N. and Nandargi, S., A study of floods in the Brahmaputra basin in India. Int. J. Climatol., 2000, 20, 771–781.

  • Goswami, B. N., Venugopal, V., Sengupta, D., Madhusoodanan, M. S. and Xavier, P. K., Increasing trend of extreme rain events over India in a warming environment. Science, 2006, 314, 1442– 1444.

  • Varikoden, H. and Revadekar, J. V., On the extreme rainfall events during the southwest monsoon season in northeast regions of the Indian subcontinent. Meteorol. Appl., 2019, 1–13.

  • Dhar, O. N. and Nandargi, S., Hydrometeorological aspects of floods in India. Nat. Hazards, 2003, 28, 1–33.

  • Shivaprasad Sharma, S. V., Parth Sarathi Roy, Chakravarthi, V., Srinivasarao, G. and Bhanumurthy, V., Extraction of detailed level flood hazard zones using multi-temporal historical satellite datasets – a case study of Kopili River Basin, Assam, India. Geomat. Nat. Hazards Risk, 2016, 8, 792–802.

  • De, U. S., Dube, R. K. and Rao, G. S. P., Extreme weather events over India in the last 100 years. J. Indian Geophys. Union, 2005, 9, 173–187.

  • Singh, Y., Ferrazzoli, P. and Rahmoune, R., Flood monitoring using microwave passive remote sensing (AMSR-E) in part of the Brahmaputra basin, India. Int. J. Remote Sensing, 2013, 34, 4967– 4985.

  • Hazarika, N., Barman, D., Das, A. K., Sarma, A. K. and Borah, S. B., Assessing and mapping flood hazard, vulnerability and risk in the Upper Brahmaputra River valley using stakeholders’ knowledge and multicriteria evaluation (MCE). J. Flood Risk Manage., 2018, 11, 700–716.

  • Jain, S. K., Saraf, A. K., Goswami, A. and Ahmad, T., Flood inundation mapping using NOAA AVHRR data. Water Resour. Manage., 2006, 20, 949–959.

  • Borah, S. B., Sivasankar, T., Ramya, M. N. S. and Raju, P. L. N., Flood inundation mapping and monitoring in Kaziranga National Park, Assam using Sentinel-1 SAR data. Environ. Monit. Assess., 2018, 190, 1–11.

  • Bhatt, C. M. et al., Satellite images for extraction of flood disaster footprints and assessing the disaster impact : Brahmaputra floods of June–July 2012, Assam, India. Curr. Sci., 2013, 104, 1692– 1700.

  • Amante, C. and Eakins, B. W., Etopo1-1 arc-minute global relief model: procedures, data sources and analysis. NOAA Technical Memorandum, NESDIS NGDC-24 ETOPO1, 2009.

  • Kakade, S. B. and Dugam, S. S., Impact of cross-equatorial flow on intra-seasonal variability of Indian summer monsoon rainfall. Geophys. Res. Lett., 2008, 35, 1–5.

  • Vellore, R. K. et al., Monsoon – extratropical circulation interactions in Himalayan extreme rainfall. Climate Dyn., 2016, 46, 3517–3546.

  • Muhammad Tahir, K., Yin, Y., Wang, Y., Babar, Z. A. and Yan, D., Impact assessment of orography on the extreme precipitation event of July 2010 over Pakistan: a numerical study. Adv. Meteorol., 2015, 2015, 1–19.

  • Goswami, B. B., Mukhopadhyay, P., Mahanta, R. and Goswami, B. N., Multiscale interaction with topography and extreme rainfall events in the northeast Indian region. J. Geophys. Res.: Atmos., 2010, 115, 1–12.

  • Prokop, P. and Walanus, A., Variation in the orographic extreme rain events over the Meghalaya Hills in northeast India in the two halves of the twentieth century. Theor. Appl. Climatol., 2015, 121, 389–399.

  • Houze Jr, R. A., Orographic effects on precipitating clouds. Rev. Geophys., 2012, 50, 1–47.

  • Yang, Y. C. E., Ray, P. A., Brown, C. M., Khalil, A. F. and Yu, W. H., Estimation of flood damage functions for river basin planning: a case study in Bangladesh. Nat. Hazards, 2014, 75, 2773–2791.

  • Das, K., Farm productivity loss due to flood-induced sand deposition: a study in Dhemaji, India, South Asian Netw. Dev. Environ. Econ., 2012.

  • Arvind, C. S., Vanjare, A., Omkar, S. N., Senthilnath, J., Mani, V. and Diwakar, P. G., Flood assessment using multi-temporal MODIS satellite images. Procedia – Comput. Sci., 2016, 89, 575– 586.

  • Jamir, T., Gadgil, A. and De, U. S., Recent floods related natural hazards over west coast and Northeast India. J. Indian Geophys. Union, 2008, 12, 179–182.

  • Goyari, P., Flood damages and sustainability of agriculture in Assam. Econ. Polit. Wkly, 2005, 40, 2723–2729.

  • Gaurav, K., Panda, R. and Sinha, P. K., The Indus flood of 2010 in Pakistan: a perspective analysis using remote sensing data. Nat. Hazards, 2011, 59, 1815–1826.


Abstract Views: 321

PDF Views: 72




  • Role of Meteorology and Local Orography on a Flood Event in the Lower Subansiri Basin and Post-Flood Changes to Land Use and Land Cover

Abstract Views: 321  |  PDF Views: 72

Authors

Partha Pratim Gogoi
School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Arugul, Jatni 752 050, India
V. Vinoj
School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Arugul, Jatni 752 050, India
Parag Phukon
Department of Geological Sciences, Gauhati University, Jalukbari 781 014, India

Abstract


Extreme rainfall in the Arunachal Himalaya has the potential to create floods in the downstream regions of Assam, with the rivers in the region exceeding their capacity and competence. High-intensity rainfall also leads to higher sediment generation in the sub- Himalayan catchment. Though floods have been incurring huge losses to both life and property frequently in Assam, there are only a few studies on the meteorological and orographic dynamics of such extreme rainfall events and their potential to create a flood. The present study highlights the pre-flood and post-flood scenario in the Lower Subansiri Basin (LSB) in Brahmaputra valley, Assam, through satellite data analysis and ground field surveys to establish linkages between extreme rainfall events and a subsequent major flood event that occurred during September 2012. We observed that the flood was mostly triggered by the extreme rainfall induced by orographic lifting of moisture-laden winds from the south. In addition to submerging an area of ~1900 km2, the flood also brought along fragile Neogene clastics that increased barren soil over the floodplains by ~47% compared to the pre-flood period, thus disrupting the agrarian economy of the region for several cropping seasons. These findings demonstrate the need for a reliable meteorological forecast for extreme rainfall as a prerequisite for developing effective flood-forecasting models in the Brahmaputra valley, which will positively contribute towards flood hazard management in the region.

Keywords


Extreme Rainfall, Flood, Meteorology, Orography, Sand Aggradation.

References





DOI: https://doi.org/10.18520/cs%2Fv118%2Fi5%2F778-785