Guest Article by Dr. Sreeja KG and Dr. Madhusoodhanan CG
January 6, 2021– An unexpected turn of the weather in the afternoon. Rain clouds gathered from the east and a sudden outpour that lasted through the evening. Heady smells of slaked earth and a welcome respite to the day’s heat. The joy of the surprise shower overshadowed by the worry of harvested paddy in gunny sacks stacked on the field bunds. The paddy which had dried to the satisfaction of the procurement agency’s rigorous moisture tests, is now again wet. Drying it will be an added, unforeseen expense.
Continue reading “Paddy farming in times of climate change – field notes”
According to India Meteorological Department (IMD), during the just concluded Post Monsoon Rainfall for 2020, that included rainfall during Oct-Dec months, India received 124.6 mm rainfall, 0.64% above the normal rainfall of 123.8 mm during the period. As per IMD[i] definition, the rainfall was thus normal.
This three-month period from Oct 1, to Dec 31 includes the North East Monsoon that mainly affects parts of South India including Tamil Nadu, Puducherry, Rayalseema, parts of Karnataka and Kerala. IMD declared on Jan 1, 2021 that the of NE Monsoon ended on Dec 31, 2020 with normal overall rainfall: TN had 6% above normal, Karnatak 13% above normal, Puducherry 32% above normal, Andhra Pradesh 33% above normal. However, Lakshadweep had 9% below normal and Kerala 26% below normal. This monsoon provides 48% of the annual rainfall of TN so it is most imp for that state.
The rainfall revived only towards the end of November, mainly due to two consecutive cyclones — Nivar and Burevi — both of which developed in the Bay of Bengal. While Cyclone Nivar crossed the coast close to Karaikal near Puducherry and brought heavy showers for the east and coastal districts of Tamil Nadu, Cyclone Burevi weakened before it reached land.
Continue reading “Post Monsoon 2020: State wise Rainfall”
One of the central themes of the lively presentations and discussion at the South India Sand Mining Dialogue was that the grain of sand is a habitat for so many lives, as so brilliantly put forward by Munmun Dhalaria, one of the panelists. Another key highlight was that Yogeshwaran, the lawyer painfully noted that sand mining laws are neither environment friendly nor people friendly and can be environment friendly only if they are people friendly.
Continue reading “South Zone Sand Mining Dialogue: The grain of sand is habitat for many lives”
Guest Article by S P Ravi
Kerala continues to witness unusual monsoon rainfall patterns for the third straight year in 2020. Kerala had witnessed its worst flood in almost a century in 2018. The 2019 flood was probably second only to the 2018 floods over the last 50 years, with many places experiencing larger floods than that in 2018. While the state did not face huge floods this year, tragedy struck in the form of the Pettimudi landslide near Munnar in Idukki district. It buried alive 70 members of plantation labourer families, making it the worst ever landslide in Kerala in terms of human causality. Kerala has also witnessed its wettest monsoon in September in this millennium with a rainfall of 601 mm, surpassing the previous highest of 526 mm recorded in 2007. The S-W monsoon period is now over and the state received 2227 mm rainfall, which is 9 percent above long term average.
Continue reading “Reservoir Operations Fail People in Chalakudy River Basin in Kerala in 2020”
India received 957.6 mm rainfall in Just concluded South West Monsoon 2020, during the scheduled 4 month monsoon from June 1 to Sept 30, 2020. This is 8.74% above normal monsoon rainfall of 880.6 as per India Meteorological Department (IMD). This is considered ABOVE NORMAL rainfall, since rainfall is in the range 4-10% above Normal rainfall. This sounds good at national level, but the situation on ground could be very different, if we see the rainfall across the country.
It is noteworthy as per even IMD, monsoon has not yet withdrawn from most parts of the country. But IMD closes its monsoon rainfall account at 0830 hours on Sept 30, so all rainfall after that hour has to be counted in “Post Monsoon” rainfall book, even though the rainfall is very much part of monsoon as per IMD.
Continue reading “Monsoon 2020: District Wise Rainfall”
Rejoinder Article by: J.Harsha
An article titled “Role of dams on the floods of August 2018 in Periyar River Basin” was published by Sudheer et al. (2019) in Current Science. A rebuttal was prepared and thanks to South Asia Network of Dams, Rivers and People (SANDRP), the same was published by SANDRP on 25th August 2020 (https://sandrp.in/2020/08/25/role-of-dams-in-kerala-floods-distortion-of-science/) for which Sudheer et al. (2019) has now furnished a response (https://sandrp.in/2020/09/19/response-of-sudheer-et-al-to-the-comments-by-mr-j-harsha-on-the-article-role-of-dams-on-the-floods-of-aug-2018-in-periyar-river-basin-kerala/).
In the rebuttal published by SANDRP, I had questioned the very basis of fitting HEC-HMS model for Periyar River Basin (PRB) by Sudheer et al. (2019), and also challenged the assumptions made by them, the methodology followed and the consequent voluminous inferences such as catchment response at Neeleshwaram (L2), virgin simulations, bank full discharges and particularly inferences that indicted nature for the flood calamity but exonerating the role of dams for the floods of Kerala in 2018.
Continue reading “ROLE OF DAMS IN 2018 KERALA FLOODS: Rejoinder of J Harsha to the response by Sudheer et al”
Sudheer, K P1,2,*, S. Murty Bhallamudi1,3, Balaji Narasimhan1,3, Jobin Thomas1, Bindhu, V M1, Vamsikrishna Vema1,4, Cicily Kurian1,
1Department of civil Engineering, Indian Institute of Technology Madras, Chennai – 600036,
2Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, USA.
3Indo German Centre for Sustainability, Indian Institute of Technology Madras, Chennai – 600036
*Corresponding Author: firstname.lastname@example.org
The authors of Sudheer et al. (2019) – hereinafter referred to as ‘authors’ – appreciate Mr. J. Harsha (hereinafter referred to as ‘commenter’) for his judgmental assessment (in his blog appeared on SANDRP website- “https://sandrp.in” on August 25, 2020, see: https://sandrp.in/2020/08/25/role-of-dams-in-kerala-floods-distortion-of-science/) of the authors’ work “Role of dams on the floods of August 2018 in Periyar River Basin, Kerala” (published in the Current Science in 2019: [DOI: 10.18520/cs/v116/i5/780-794]). As mentioned in Sudheer et al. (2019), the primary objective of the article was to examine whether the early release of the water stored in the reservoirs would have attenuated the flood peaks, and if so, what would have been the extent of the attenuation, in the context of debates and discussions in the social, political, as well as scientific domains based on non-sequitur speculations. Accordingly, the authors designed a scientific exercise using a widely used hydrological model (HEC-HMS) to understand the role of the dams in the Periyar River Basin (PRB) in the 2018 flooding situation.
Continue reading “Response of Sudheer et al to the Comments by Mr. J. Harsha on the article, “Role of dams in the floods of Aug 2018 in Periyar River Basin, Kerala””
In the ongoing South West Monsoon, India received 44 year old high surplus rainfall of 327 mm in just concluded Aug 2020, 26.6% above normal rainfall of 258.2 mm. This helped the total June-Aug 2020 rainfall to achieve 10% surplus, with actual rainfall 780.3 mm, 69.9 mm higher than normal rainfall of 710.4 mm. In June the country received 18% above normal rainfall and in July it received 9.9% below normal rainfall, the rainfall at the end of June was just 1.1 mm above normal. Thus almost the entire surplus rainfall is thanks to the rainfall during Aug 2020. The rainfall distribution has however, been far from normal that these figures suggest, as we can see from the state wise and district wise figures below.
Continue reading “District wise rainfall in June-Aug 2020 in India”
Guest Article by: J.Harsha
Introduction: In August, 2018, devastated floods occurred in the southern Indian state of Kerala that led to widespread death and destruction to livelihoods. One of the worst affected basins was Periyar River Basin (PRB). While investigating the role of dams in the devastating floods, an article titled, “Role of dams on the floods of August 2018 in Periyar River Basin, Kerala” by Sudheer et al., (2019) was first published in the Current Science1 Journal brought out by Indian Academy of Sciences, Bengaluru, India on 10th March 2019. The journal article by Sudheer et al., (2019) adopts hydrological model to investigate the role of dams in the occurrence of floods in PRB and concludes that dams had less or little role in the occurrence of floods in comparison to the natural reasons. However, when the article was reviewed, it was found that the authors Sudheer et al., (2019) had made fallacious assumptions, errors in their methodology, adopted poor data quality and they have arrived at erroneous inferences and conclusions such as exonerating the role of dams in Kerala floods but indicting the nature as the cause of floods. This review article therefore, using RS & GIS (Remote Sensing and Geographical Information System) techniques challenges their inferences that is based on fallacious assumptions, accumulated errors in their methodology and the poor data quality fed into the hydrological model.
Continue reading “Role of dams in Kerala floods: Distortion of Science”