The Indian Meteorological Department (IMD) was formally constituted in 1875. Both before this formal organisation came into being and after its establishment, a series of initiatives were taken in the field of weather observation and their documentation and analysis. Notable examples were the first meteorological observations at the Madras observation in the late 18th century , setting up of a large number of rain gauges in the 19th century and the compilation of their data by Blanford (1886) the first Meteorological Reporter to the Government of India, the formulation of the structure of the tropical cyclone by Paddington (1848) in Calcutta , the meteorological observations relating to the total solar eclipse (1898) organized by Eliot, the introduction of upper air observation with pilot balloon and Dines meteor graph in the early 20th century and the radiosonde observation from the 1940’s.

There were also many field observation campaigns on thunderstorms and nor’wasters in the 1920’s, 30’s and 40’s. In this series of initiatives we can place the acquisition of RADARs (Radio Detection and Ranging) for weather observation in the early 1950’s, making the IMD one of the pioneers in the world in the area of Radar Meteorology.

The History of Radar Meteorology in India can be traced back to the days of the High frequency Ionospheric Sounders. Working with these, Prof S.K. Mitra and his group at the University of Calcutta in the 1930’s discovered a layer of echoes below the D and E regions of the ionosphere and termed it the “C-region of the Ionosphere”. It was shown much later that these echoes were from the un-ionised layers of the atmosphere and occurred due to scattering form refractive index in homogeneities. These are exploited nowadays for various studies of the atmosphere.

Mitra’s work was before the invention of pulsed microwave RADAR which happened during World War II. Radar played a crucial role in the war and the development of radar was hastened by the needs of war.

Meteorologists found that radar gave echo returns from rainfall and took advantage of them for studies in meteorology. In India, during the war, the Royal Air Force used military radars which gave, as a by product, information of meteorological interest, notably on anomalous propagation (a phenomenon related to low- level temperature and humidity profiles in the atmosphere) of radio waves over very long distances across the Bay of Bengal and the Arabian sea.

Soon after the war, IMD acquired war disposal (military) radars for gaining first-hand experience and initiating research in Radar Meteorology. These were the Baby Maggie radars (operating frequency 200 MHz) used to track radio sound balloons for wind measurement, the AN/APQ-13 (10 Ghz, wavelength 3 cm, called X – band )) and SCR-717c (3 GHz, 10 cm, S-band ) for weather observations. The latter was used at Pune effectively in a mobile configuration with horizon to horizon scanning to study the melting band in stratiform monsoon precipitation. The first radar to be acquired for operational use was the Decca Type 41 radar (an aircraft tracking radar adapted for meteorological use) installed at Dum Dum Airport (Kolkata) in 1954. More such radars were installed at other airports, the main purpose being to detect thunderstorms in the vicinity for warning aviators. The first radar designed specifically for meteorology, the AN/CPS-9 (Xband) was obtained through a US aid programme and installed in New Delhi (Safarjang) in 1957.

History of Radar goes much ealier than this. Lot of surplus equipment left by Americans after the World War II were also bought almost by weight with the foresight of officers. Two Radars were sent to Pune and two were kept in Delhi. A special, small building was made on the other side of the Safdarjang Airport. The tower still stands as witness of RADAR. It was the most powerful Radar in entire Asia. China and Japan did not have Radar till then. A large tower of 75 ft was erected. The Radar arrived at Palam Airport and truly brought to the building in bullock carts. It was a problem how to put it on a 75 ft tower. No helicopter took up that job as they were not specialised for this kind of assignments. Cranes to handle this kind of jobs were not available at that time. The standard, indigenous chain pulley system was used by the highly skilled contractors who did the job.

A Japanese X-band radar was installed at Kolkata and a similar one at the Rain and Cloud Research Unit of the National Physical Laboratory at New Delhi. The latter came in due course under the control of the Indian Institute of Tropical Meteorology, Pune. All these were used by various researchers in the IMD and the Rain and Cloud Unit to document and classify convective clouds and thunderstorms notably nor’westers of estern India and associated phenomena (such as and his) and build up useful climatologies of their properties.

The Rain and Cloud Unit radar was also useful in cloud physics and weather modification studies. An important early result from these radars was the finding (supported by high-flying jet aircraft observations) that monsoon clouds in much of north India extended to considerable heights sometimes overshooting the tropopause. This was a new finding because ( in the absence of observations) it was thought by many meteorologists earlier, that monsoon rain is mostly of warm origin and clouds rarely extend much beyond the freezing level. This warm rain hypothesis was largely true of monsoon rain on the west coast of peninsular India, but not necessarily in other parts of India. More quantitative studies such as the size distribution of radar echoes and fractal dimensions, leading to inferences of a more fundamental nature also became possible during the 1970s and later with the installation of new radars. Quantitative estimation of precipitation and comparison with rain gauges were also carried out though these were not operationalised at that time.

In the late sixties, an indigenous capability to manufacture radars was established in Bharat Electronics Ltd (BEL). X – band and later S-band radars were supplied to IMD by BEL.

Considering the importance of detection and tracking of tropical cyclones affecting the Indian coasts, a group of 10 S-band radars was planned. The first one was installed at Visakhapatnam in 1970. Accurate tracking of cyclones leading to more accurate forecasts is probably the greatest contribution weather radar has made in India. Due first impact of the new radars was Ehen a cyclone crossing the Tamil Nadu coast was tracked for over 24 hours in 1972 for the first time in India, leading to a good forecast saving many lives and property damage. This was appreciated by the public and the State Government.

The observation of cyclones also enabled study of the structure and other features of cyclones. The use of multiple radars and the Indian National Satellite (INSAT) which became available in the 1980s led to reliable tracking of cyclones and further improvement of forecasts and timely warnings.

These radars were capable of only mapping the “radar reflectivity factor” and there was no means of determining the velocity of air motion in the echoes. The maximum wind velocity in a cyclone and the radius of maximum winds (RMW) are important parameters for assessment of intensity of the cyclone and prediction of the storm surge which is the most destructive phenomenon in the cyclone. A technique was developed in the IMD for estimating the RMW from radar imagery and implemented in the 1980s. The determination of maximum velocity had to wait for the installation of Doppler radars at the turn of the century.

In the 1990s IMD took a major step forward to introduce digital Doppler Radars in its network gradually replacing the old analog reflectivity-only radars. Imported S-band digital Doppler radars are functioning in the last 10 years at Chennai, Machilipatnam, Viskhapatnam and Kolkata as part of the Cyclone Detection network. Simultaneously under a collaborative programme the Indian Space Research Organisation (ISRO) designed an indigenous Doppler radar for IMD and it has been manufacture a Mark-II version for IMD, ISRO and other organisations.

The digital and Doppler capability increases the versatility of the radars several fold. Besides reflectivity factor which is the basic output of all radars, these give additional output of echo velocity and its variance. Using these outputs it is possible to derive several products of operational meteorological interest. Distribution of rainfall rates, accumulated rain over a period of time, vertical profile of wind, signatures of cyclones and tornadoes, maximum wind in cyclones, wind shear and turbulence, probability of severe weather and hail and the likely size of hailstones are among the important products. These derived products make use of several assumptions and therefore calibration of the radar and validation of products is a continuing process. Radar displays are transmitted by internet and some of these are available to the public.

Digital radar data are being assimilated into Numerical Weather Prediction (NWP) models. This opens up numerous possibilities for weather analysis and forecast of various weather phenomena especially on the “meso-scale”. Besides operational use, meteorological research using radar data in conjunction with other surface- and satellite meteorological data by various organisations is being pursued.

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In what may cause fresh embarrassment to the Intergovernmental Panel on Climate Change (IPCC), it has emerged that its warning about ice disappearing from the world’s mountain tops was based on a student’s thesis and an article published in a mountaineering magazine.

Earlier, the IPCC had to issue a humiliating apology over its inaccurate claim that global warming will melt most of the Himalayan glaciers by 2035, saying it was based on a “speculative” article published in New Scientist.

In its recent report, IPCC stated that observed reductions in mountain ice in the Andes, Alps and Africa was being caused by global warming, citing two papers as the source of the information.

However, it has emerged that one of the sources quoted was a feature article published in a popular magazine for climbers which was based on anecdotal evidence from mountaineers about the changes they were witnessing on the mountainsides around them, The Telegraph reports.

The other was a dissertation written by a geography student, studying for the equivalent of a master’s degree, at the University of Berne in Switzerland that quoted interviews with mountain guides in the Alps.

After the surfacing of the fact that IPCC has been using unsubstantiated claims and sources for its warnings, sceptics have cast doubt over the validity of the IPCC and have called for the panel to be disbanded.

“These are essentially a collection of anecdotes. Why did they do this? It is quite astounding. Although there have probably been no policy decisions made on the basis of this, it is illustrative of how sloppy Working Group Two has been,” Professor Richard Tol, one of the report’s authors who is based at the Economic and Social Research Institute in Dublin, said.

“There is no way current climbers and mountain guides can give anecdotal evidence back to the 1900s, so what they claim is complete nonsense,” he added.

However, scientists from around the world leapt to the defence of the IPCC, insisting that despite the errors, the majority of the science presented in the IPCC report is sound and its conclusions are unaffected.

British Climate Secretary Ed Miliband on January 31 came out in strong support of the R K Pachauri led UN panel, slamming the “siren voices” gunning for the panel over allegations of exaggeration of global warming claims.

Extending support to the IPCC, Miliband said the effects of concentration of carbon dioxide in the atmosphere, which is at highest levels in 6,000 years, were all too well known and that “we know there are observed increases in temperatures and observed effects that point to the existence of human-made climate change”.

“Mistakes and attempts to hide contradictory data had to be seen in the light of the thousands of pages of evidence in the IPCC’s four-volume report in 2007,” he said referring to the IPCC report that has been surrounded by controversies.

“It’s right that there’s rigour applied to all the reports about climate change, but I think it would be wrong that when a mistake is made it’s somehow used to undermine the overwhelming picture that’s there,” he told the Observer.

The most recent accusation against the panel’s work is that its chairman, Rajendra Pachauri, may have known before the Copenhagen summit that its assessment report had seriously exaggerated the rate of melting of the Himalayan glaciers.

However, Miliband said he believed the IPCC was on right track. “Its worth saying that no doubt when the next report comes out it will suggest there have been areas where things have been happening more dramatically than the 2007 report implied”.

Miliband said the danger of climate scepticism was that it would undermine public support for unpopular decisions needed to curb carbon emissions, including the likelihood of higher energy bills for households and issues such as the visual impact of wind turbines.

“There are a whole variety of people who are sceptical, but who they are is less important than what they are saying, and what they are saying is profoundly dangerous,” he said.

Miliband said if the UK did not invest in renewable, clean-energy, it would lose jobs and investment to other countries, have less energy security because of the dependence on oil and gas imports and contribute to damaging temperature rises for future generations.

“Everything we know about life is that we should obey the precautionary principle; to take what the sceptics say seriously would be a profound risk,” he said.

Admitting the Copenhagen summit was a “disappointment,” Miliband said there were, however, important achievements including the agreement by countries responsible for 80 per cent of emissions to set domestic carbon targets.

“There’s a message for people who take these things seriously, don’t mourn, organise,” said Miliband, who has previously called for a Make Poverty History-style mass public campaign to pressure politicians into cutting emissions.

Lord Smith, the Environment Agency chairman, said: “The Himalayan glaciers may not melt by 2035, but they are melting and there’s a serious problem that’s going to affect substantial parts of Asia over the course of the next 100 or more years”.

Meanwhile, after ‘Glaciergate’ and errors in Climate Change report spawned attacks, UN Climate Chief R K Pachauri faced demands from Britain’s chief scientific adviser for “more honest” disclosure of the uncertainty of predictions about the rate of global warming.

John Beddington also said the impact of global warming has been exaggerated by some scientists.

Another top British scientist Mike Hulme raised questions whether Pachauri of India should continue to head the Intergovernmental Panel on Climate Change (IPCC).

In the wake of an admission by IPCC that it grossly overstated the rate at which Himalayan glaciers were receding, Beddington told ‘The Times’ that climate scientists should be less hostile to sceptics who questioned man-made global warming.

He also condemned scientists who refused to publish the data underpinning their reports.

Beddington said that public confidence in climate science would be improved if there were more openness about its uncertainties, even if that meant admitting that sceptics had been right on some hotly-disputed issues.

Pachauri’s ‘voodoo science’ remark to slam India’s Environment ministry over the Himalayan glacier issue drew more flak from another scientist.

Hulme, Professor of Climate Change at the University of East Anglia, criticised Pachauri for his dismissive response last November to research by an Indian group suggesting that the UN body had overstated the threat to the glaciers.

Pachauri described it as “voodoo science”. “Pachauris choice of words has not been good. The question of whether he is the right person to lead the IPCC is for the 193 countries who make up its governing body. It’s a political decision.” Prof Hulme said.

Beddington said that the false claim in the IPCCs 2007 report that the glaciers would disappear by 2035 had exposed a wider problem with the way that some evidence was presented.

“I dont think its healthy to dismiss proper scepticism. Science grows and improves in the light of criticism. There is a fundamental uncertainty about climate change prediction that cant be changed,” said.

“Certain unqualified statements have been unfortunate. We have a problem in communicating uncertainty. There’s definitely an issue there. If there wasnt, there wouldnt be the level of scepticism. All of these predictions have to be caveated by saying, Theres a level of uncertainty about that.”

Beddington said that particular caution was needed when communicating predictions about climate change made with the help of computer models.

“Its unchallengeable that Carbon Dioxide traps heat and warms the Earth and that burning fossil fuels shoves billions of tonnes of Carbon Dioxide into the atmosphere. But where you can get challenges is on the speed of change.

When you get into large-scale climate modelling there are quite substantial uncertainties. On the rate of change and the local effects, there are uncertainties both in terms of empirical evidence and the climate models themselves.”

He said that it was wrong for scientists to refuse to disclose their data to their critics: “I think, wherever possible, we should try to ensure there is openness and that source material is available for the whole scientific community.”

He added: “There is a danger that people can manipulate the data, but the benefits from being open far outweigh that danger.”

Critically polluted industrial areas are not just an environmental challenge, but they are a public health challenges. 85% of big industrial clusters in India are health hazards as air, water and land pollution levels are not fit for human habitants. The Central Pollution Control Board (CPCB) released a study Criteria for Comprehensive Environmental Assessment of Industrial Clusters ranking the environmental pollution in 88 industrial clusters across the country. The study formulates a comprehensive environment pollution index (CEPI) on the basis of water, land and air pollution. All available data on water and air pollution, biodiversity conservation, land degradation, ecological damage and waste management has been used to make this assessment. The exercise would be undertaken once in two years.

The study, Comprehensive environmental assessment of industrial clusters, undertaken by IIT Delhi and the CPCB, found that the environmental pollution levels in 10 major industrial hubs had reached a “very alarmingly high” level. This list includes Ankleshwar and Vapi in Gujarat , Ghaziabad and Singrauli in Uttar Pradesh, Korba (Chhattisgarh), Chandrapur (Maharashtra), Ludhiana (Punjab), Vellore (Tamil Nadu), Bhiwadi (Rajasthan) and Angul Talcher (Orissa).

Central Pollution Control Board (CPCB) identified 24 critically polluted areas earlier based on scientific criteria and design Action Plans for each area. CPCB has identified another 36 clusters/ areas which have been reported as having significant industrial activities and related environmental pollution problems. CPCB will define critically polluted area based on the Environmental parameters index and prioritization of economically feasible solution through adequate action plan formulation for environmental sustainability problem area faces. Now the exercise will be done in measurement, monitoring and modeling, thus capturing various dimensions of pollution, in some states to know how the course of pollution is going to evolve. Base level information will be gathered so that a robust methodology can be developed after this exercise.

Air Quality Index, Water Quality Index and Land Quality Index can be recorded, but there is always a danger in the uni-dimensional index approach and one might loose some information embedded into it. The practical suggestion would be to evolve an EPI index like western countries where literacy, life expectancy, per capita income etc. are included.

The problem in most critically polluted areas is highly serious, as the effluent from industries is discharged at night. Villages in polluted areas of Vapi and Ankleshwar in Gujarat have not seen clean drinking water since a long time and water in Vapi Town is not potable. High degree of asthma cases and irritation, particularly in eyes are prevalent among people.

CPCB initiated a programme to identify problem area from pollution point of view for taking concerted action and for being centrally monitored at the national level to improve the environment such as air and water quality data, public complaints, ecological damage, and visual environmental conditions Central Pollution Control Boards (CPCBs) and Sate Pollution Control Boards (SPCBs) prepared a list of the potential area. The issue was discussed in depth in the 29th Conference of Chairmen and Member Secretaries of SPCBs/PCCs held in May 1989, and 10 critically Polluted Areas (CPAs) were identified to evolve a comprehensive time bound programme for each of the problem areas with respect to improvement of air and water quality. 14 more areas got added subsequently making the total number of identified CPAs as 24. An Action Plan will be prepared for the industrial clusters/ areas which would be identified as CPAs. These Action Plans will help in prevention and control of pollution and to restore the environmental quality of CPAs. Action Plans shall be prepared with the help of all the stakeholders and after determining the comparative effectiveness of alternate plans and policies.

EPI is a rational number to characterize the quality of the environment at a given location following the algorithm of source, pathway and receptor. As the EPI increases, an increasingly large percentage of the population is likely to experience increasingly severe adverse health effects. Environmental aspects are identified and assets of core pollutants adopted for each industrial cluster are created.