eChapters

Jasmines constitute a group of traditional flower crops which are commercially grown for their fragrant flowers and essential oil production. There are trailing, climbing, and erect growing species and cultivars in the genus Jasminum. The genus Jasminum comprises of more than 200 species which are known to occur in different tropical and subtropical regions of the world. The countries growing Jasmines on a commercial scale are India, France, Italy, Morocco, Algeria, North Africa, Egypt and Spain. More than 80 Jasminum species are found in India, of which only four species viz., Jasminum sambac (Mogra / Gundumalli), Jasminum auriculatum (Jui / Mullai), Jasminum multiflorum syn Jasminum pubescens (Kunda / Kakda) and Jasminum grandiflorum (Jai / Pitchi) are widely used for commercial cultivation. Jasmines are commercially grown in many parts of the country as a dry land crop. The leading states in jasmine production are South Indian states like Tamil Nadu, Karnataka and Andhra Pradesh. In India, the commercial cultivation of jasmines are popular in Athoor, Coimbatore, Dharampuri, Dindigul, Erode, Krishnagiri, Madurai, Nilakottai, Periakulam, Salem, Thiruchirapalli, Thirunelveli, Thiruvallur, Tirumanagalam, Vellore, Virudhunagar etc. in Tamil Nadu; Bangalore, Bellary, Kolar, Mysore, Shimoga, Tumkur etc. in Karnataka ; Hyderabad, Khammam, Mahbubnagar, Mancherial, Ranga Reddy, Sangareddy, Vikarabad, Warangal Rural, Yadadri etc. in Telangana; Anantapur, Chittoor, Cuddapah, East Godavari, Guntur, Krishna, Kurnool, Nellore, Prakasam, West Godavari etc. in Andhra Pradesh; Ahmednagar, Aurangabad, Pune, Sangli etc. in Maharashtra; Ahmedabad, Anand, Bharuch, Bhavnagar, Kutch, Vadodara etc. in Gujarat; Gazipur, Jaunpur, Kannauj etc. in Uttar Pradesh; Ajmer, Jaipur, Kota, Udaipur etc. in Rajasthan; Panskura Ranaghat etc. in West Bengal; Guwahati, Hoja, Jorhat etc. in Assam ; and parts of Punjab and Delhi. Jasmines contributes markedly to the national economy and it is estimated that annually more than 20 crores worth of jasmine flowers are produced and traded in India and are also exported to countries like Malaysia, Singapore, Sri Lanka, UAE and United States (Safeena et al., 2017).

Marigold (Tagetes spp.) is an important annual flower crop; native to Central and South America especially Mexico and belongs to family Asteraceae (Compositae). It is commonly known as “Gainda” in India and also called as “Friendship Flower” in United States of America. Loose flowers of marigold are in great demand throughout the year. It is commercially grown in tropical and subtropical regions of India owing to its ease in cultivation, hardy nature, wider adaptability and year round availability of single, semi-double and double flowers of vibrant colours. Marigold is grown over an area of about 66.09 thousand hectares with production of 603.18 thousand MT loose flowers in India. Major states involved in loose flower production of marigold are Karnataka, Madhya Pradesh, Gujarat, Andhra Pradesh, West Bengal, Maharashtra, Haryana and Chhattisgarh. In India, Assam is the only state, which produces marigold for both cut as well as loose flower purpose on an area of about 0.61 thousand hectare (Anonymous, 2016a).

Marigold is a cross-pollinated flower crop and it is pollinated by insects (Kaneko et al., 1990). It bears terminal and solitary inflorescence, known as head or capitulum, which possesses long and hollow peduncle with swollen apex and campanulate involucres (Setshogo, 2005). Capitulum consists of peripheral ray florets and central disc florets. Ray florets are pistillate, ligulate, sessile, epigynous and zygomorphic, whereas, disc florets are bisexual, tubular, sessile, epigynous and actinomorphic (Subrahmanyam, 1996 & Setshogo, 2005).

African marigold (Tagetes erecta L.) is a diploid species (2n = 2x = 24), while, French marigold (Tagetes patula L.) is a tetraploid species (2n = 4x = 48) with basic chromosome no. of x = 12 as revealed by breeding work of various researchers (Towner, 1961, Chen and Lin, 1981, Chen and Lin, 1982, Serrato-Cruz et al. 2000, Zhang et al., 2011). Tagetes erecta and Tagetes tenuifolia are diploid species, whereas, Tagetes patula, Tagetes minuta, Tagetes biflora and Tagetes remotiflora species are tetraploid in nature (De, 2017). On the basis of floral morphology; three different types of male sterile systems i.e. apetaloid, petaloid and gynomonoecious types was observed in African marigold (Prakash et al., 2016). Out of these, apetalous male sterility (femina type) is more reliable and preferred over petalous male sterility because later is more prone to break down (Goldsmith, 1968 & Janakiram, 2004). Apetaloid male sterility was controlled by single recessive gene (Prakash et al., 2016). A monogenic recessive male sterile apetalous mutant was detected from T. erecta population by Khoshoo (1979). Cyto-genetic male sterility is also found in marigold (De, 2017). Petaloid and gynomonoecious male sterile systems were controlled by cytoplasmic inheritance (Prakash et al., 2016). In marigold, cytoplasmic genetic male sterile lines were also developed for commercial production of F_l sterile hybrids (Pratibha et al., 2000).

Lotus being a national flower of India, is closely associated with religion and culture. It is a perennial, aquatic crop that is grown and consumed throughout Asia. The edible parts of lotus are Leaves, flowers, seeds and rhizomes, and the flowers are also used in religious ceremonies. Lotus flowers are also, used for extraction of perfumes. It is one of the oldest plants in the world Archaeologists in China found Lotus seeds with estimated ages of 5,000 years in 1972 in Yunnan Provincelagoons.

During the pre-historic period, the South India Dravidians used lotus flowers (pundarika) as their food, much earlier than the people of the Indus Valley civilization (3000-2000 BC). However, there is no evidence of lotus being present during the Indus Valley culture of the Mohenjo Daro and Harappa period in northern India. The Rigveda reference that lotus was made by the Aryans (2000-1500 BC) wherein it is also mention that lotus can be used as food. Subsequently, lotus was mentioned in the Vedas, Upanishads, Puranas, Slokas, plays and other ancient Sanskrit literature. The lotus symbol is not only mentioned in the scriptures of Hinduism but it also occurs in the Buddhist and Jainism literature.

In the Arthasastra (350-300 BC) by Kautilya, the great diplomat during the golden age of Chandra Gupta, it is recorded that one of the varieties of sandal wood possesses the fragrance of lotus. The Mughal kings were also attracted towards the beauty of lotus. While describing Agra, the Mughal king Jehangir (1605-1627 AD) in his memories Tuzuk-i-Jehangiri, mentioned a memorable scene of a tank full of exquisite red lotus flowers, the like of which he had not seen before.

Floriculture is a high value industry. It is increasingly regarded as a feasible diversification option from traditional field crops due to increased per unit returns and increasing habit of ‘Greeting with Flowers’ during all the occasions. With increasing awareness among consumers and pressure from the artificial floral products on the fresh flower industry, and continued competition even amongst the growers, whole salers and retailers, quality is becoming increasi ngly important. The aspects related to visual quality of the product are the main determining indices of consumer’s acceptability of flowers.

The important flower crops in the international market are rose, carnation, lisianthus, chrysanthemum, gerbera, hydrangea, gladiolus, gypsophila, bird of paradise, orchids, anthurium, tulip and lilies etc. Cut flowers have the highest economic value and are the most perishable. Their high respiration rates, rapid deterioration, and susceptibility to damage require the utmost care during postharvest handling for quality maintenance. The post-harvest losses can be both, quantitative as well as qualitative, which ultimately result in loss in terms of its monetary value.

Floriculture industry is facing main problem due to highly perishable nature of its flowers which demand for appropriate post-harvest handling techniques to maintain the quality. With changing scenario in international floriculture trade, perfection in post-harvest technology is mandatory to offer quality plant products to the consumers round the year. The post-harvest life of cut flowers and flowering pot plants can be extended relatively by a range of treatments and technologies. Quality factors that influence the post- harvest keeping quality and flower longevity are environmental factors as well as the influence of the pathogenic organisms. Due to perishable nature of cut flowers, huge post-harvest loss is there which ranges from 30-50 per cent. Qualitative losses which include consumer acceptability of fresh produce are much more difficult to measure than quantitative losses. Quantitative losses can occur during the entire post-harvest and marketing chain due to lack of proper post harvest handling (Bhattacharjee, 2006). These losses could be on a higher side, which might be due to lack of knowledge on ‘post-harvest handling’ of cut flowers and proper infrastructure for post-harvest management and storage. However, all these losses can only be minimized by proper technique of harvesting, post-harvest handling, packaging, storage, marketing and value addition of flowers.

Flowers and various parts of the plant have been used for decoration and to commemorate various religious, festive, matrimonial and social gathering events in day to day life. The main drawback of fresh flowers and foliage is being highly perishable and delicate which cannot retain their beauty for longer durations. Moreover fresh flowers are not available round the year which can be overcome by the dehydration and drying techniques. Since ancient times, in Egyptian pyramids, fragrant dried flowers and herb garlands were encased along with mummified bodies. Japanese people created “Oshibana”, the “preserved flower art” of enduring designs to retain the exquisite beauty of the living plants centuries ago.

Later on, this craft making technique spread from Japanese to Victorian England because of their beautiful long lasting appearance. During middle ages monks dried flowers, foliage, and herbs for use in decorative motifs or for colouring their handprinted books.

Dried flower arrangements have been popular in Europe for centuries, and as early as 1700 AD, colonial Americans used dried flowers to brighten their homes, especially during the dark winter months.

Earlier botanists practiced dried flowers in the form of herbarium for the purpose of identification of various plant species. Though drying of flower was well known even in the past but for the first time the flowers were dried commercially in Germany (Sankari and Anand, 2014).

Floriculture has flourished with a considerable growth and a useful crop diversification option, particularly for small farmers over the past three decades. The commercial production of the cut greens has started in India in recent years and has huge demand in the market. They are suited for year round production with low investment and less care and maintenance. Cut greens or fillers are an important component of the floricultural industry and their commercial value depends on vegetative characters, such as stem length, leaf colour, density and side branching. Cut foliages (leaves and stems), which are attractive in form, colour and freshness, are lasting and in great demand. They have various other uses in making attractive fresh floral designs and floral arrangements, such as bouquets, wreaths, decoration of house interiors, etc. Evergreen plants with green, silver or variegated leaves are usually used and species with berries are now also becoming popular. Fillers are critical components in most arrangements as the flowers themselves,used to increase the volume and size of the bunch and provide colour contrast. These floral produce have various other uses in making attractive fresh floral designs and floral arrangements, such as bouquets, wreaths, decoration of house interiors, etc. Colour, freshness, stem length, freedom from pests, fragrance and vase life are important quality aspects of fillers. In the International market, fillers accounts for about 16 percent of the total trade by volume with an annual turnover of more than Rs 800 crores including selling of ornamental leaves, filler flowers, dry and dyed flowers along with berries and capsules. On the contrary, fillers representvery less quantum with poor quality in the domestic market and are unsuitable for cut flower bouquets. Their share in the market is very low and fetches nominal rates.

Flower arrangement is the art of using plant materials and flowers to create an eyecatching and balanced composition or display. Among all art forms, flower arrangements today take as prominent a place. The art engages ones personal involvement in welcoming guests and bringing cheer to the surroundings. It is rightly said, “Flowers are the music of the ground. From earth’s lips spoken without sound. “Professionally designed floral designs, arrangements or artwork incorporate the elements of floral design: line, form, space, texture, and color, and the principles of floral design: balance, proportion, rhythm, contrast, harmony, and unity.

Composition of Arrangements

There are a few compositions of flower arranging that should be considered. Once we understand these we can create so many different styles and our floral designs will have that professional look.

All higher plants have some kinds of aroma or flavor in their various parts, which includes roots, stems, leaves, flowers and fruits. This flavor and aroma in a particular plant part due to the presence of some specific essential oils present in special glands in it (Chadha and Choudhury, 1989). Essential oils arethe concentrated liquid, which is highly concentrated and water insoluble liquid (hydrophobic) and it is also known as ethereal or volatile oils, which are fragrant oily liquid that are extracted from the various parts of the plants. Generally they are organic compounds like hydrocarbons likealcohols, aldehydes, esters, ketones and phenols. An essential oil is “essential” in case that it contains the essence of the different fragrance, and the properties of the plants from which they are derived. All though all ornamental plants have some aroma but only few of them are used commercially in perfumes, flavor and cosmetic industries. The essential oil demand by fragrance industry is 60%, flavour industry 20% and pharmaceutical industry 20%. In all the perfumes, rose oil is one of the best and costliest perfume. The first recorded reference of rose perfume is in CharakSanghita. The credit for discovery of rose perfume was given to Queen Noor Jehan mentioned in the book written by Md. Achem of King Jahangir’s regime.

The volatile oils showed the different kinds of biological activities including the antibacterial, antioxidant, antiviral, insecticidal, etc. These oils are also used for cancer treatment, while some other has been used for the food preservations, aromatherapy, and in the perfumery industries. Thus, in the day to day life a large spectrum of usage the essential oil and aroma industry has a bright future. Yet the known applications of essential oilsare opening up ofmore areas which will benefit the industry.

1.1 Weather Parameters

The atmosphere is a gaseous component surrounding the earth as an integral part and its interaction with ocean (water bodies), other planets of the solar system and land (Earth) generates one physical product namely weather elements (temperature, pressure, wind, humidity, precipitation, etc.,) and these form the weather and climate of the Earth. The process of generation of weather and climate of the region is purely natural and cannot be modified by the human being. But they can do adaptation to the existing climate and weather for their sustainable life. The weather can be defined as day to day change in the atmosphere in terms of heat and moisture exchange, while the climate is average of long period weather covering larger area or a region.

The particular climate of a region dictates/permits the genesis of a particular bio-organism in that domain and this selected organism’s growth and multiplication are triggered by the prevailing weather of that particular climate. Hence weather parameters of the atmosphere are very important to human being and other organisms of the Earth. The details on weather elements are given in question and answer section of this book (Annexure-I)

The climate, the past weather event that existed over larger region and covering long years of more than 30 years is very important for the emergence and successful sustenance of an organism including human kind. Normally scientists talk about environment and this includes not only the soils but also the climate of the particular region. Based on this, during 1989, the Planning Commission of India divided the entire India in to 15 agro-climatic zones based on physiography and climate. This division is only for planning purposes. Subsequently under NARP, the Indian Council of Agricultural Research (ICAR), New Delhi in consultation with the Planning Commission, requested all State Agricultural Universities (SAU) to divide their State in to different sub climatic zones considering soils, temperature and other weather parameters preciously with in the major agroclimatic zone of India in which the concerned State falls. Accordingly, each SAU has divided their State into different agro-climatic sub-zones and this resulted in 129 agro-climatic sub zones in India and limited to 127 and these all fall within 15 agro climatic zones of India as done by the Planning Commission of India.

The National Bureau of Soil Survey and Land Use Planning (NBSS&LUP), Nagpur not satisfied with this division, considering soils, temperature, rainfall, vegetation and all factors responsible for ecosystem (bio-climate, length of growing period, moisture index) divided the whole India in to 20 agro-eco regions by 1992 and revised preciously again by 2015 (Mandal et al., 2016) and the revised approach is being considered as scientific tool and taken for micro-level planning in India now and those are discussed at this chapter.

The subject on micrometeorology deals with small scale meteorology of near ground surface with its related elements of both physical and biological processes. When this micrometeorology is integrated for crop production purposes, then it becomes crop micrometeorology, which is very important in the science of agricultural climatology. This crop micrometeorology gets varied with the architecture of the crops grown, available soil moisture, agronomical practices followed, soil texture, topography of the area, the nature of climate and weather that prevails etc. The soil surface heat, exerts a profound frictional effect on wind movements and hence it is different from the air layers at higher levels. These special features constitute the microclimate, which is modified compared to a flat bare surface by factors like topography, nature of soil surface, presence of vegetation and type of vegetative cover. The presence of crop canopy leads to distinct differences in the thermal and humidity regimes of the soil, the air layers immediately above it and the distribution of radiation and wind profiles inside the canopy. The study on the physical exchanges of the transfer of heat, momentum and moisture in the microclimatic region is called as micrometeorology (Venkataraman and Krishnan, 1992).

Radha Krishna Murthy (2002) reported that the micrometeorology is the micro scale of both the physical and meteorological factors that are taking place within the ecosphere. The ecosphere means the area between just above the crop canopy and just below the root zone of a crop. Further he was on the opinion that the microclimate of valley is important as compared to the entire climate of the mountain for the bio-life of valley. For the crops purpose, the microclimate is the climate of the ground surface to top of the crop canopy or otherwise it can be called as crop’s climate, a modified one from the Stevenson’s Screen climate/weather observation.

4.1. Introduction

Many countries have set up a network of agrometeorological observatories to regularly record important weather parameters such as clouds, rainfall, surface temperature, humidity, wind and wind direction, solar radiation, soil moisture, temperature and humidity profile of the atmosphere, etc. The observation process is performed either manually or through Automatic Weather Stations (AWS).

This recorded information is used for weather forecasting, natural resources management and for tracking agricultural production. However, these networks, which handle data of high spatial climate variability, are typically less robust than they should be. Moreover, the agrometeorological data collected from different ground stations is not transmitted in real time to a central collection point which limits the use of information.

Satellite remote sensing technology is an alternative system that is gaining popularity in the recent times which has allowed us to obtain frequent and precise measurements of vital agrometeorological parameters such as rainfall, solar radiation, temperature, evapotranspiration, albedo etc. Satellite data has many advantages over traditional ground stations, such as high spatial resolution (50 m–5 km), wide spectral bandwidth range (0.4–3.75 um) and high temporal frequency (even half an hour) and the prospect of collecting data from remote areas. In addition to routine repeated observations, satellites often provide synoptic views of the earth’s surface from space on a wide scale and have archive of information to create baseline data.

The preparation, planning and use of agricultural technologies for agriculture, needs application of agricultural meteorology. The role of agrometeorology in the last three decades has increased in terms of increasing food and nutritional security for the burgeoning population and natural resource management particularly in the context of global climate change. Agrometeorology can help to minimize inputs, thus clarifying the contribution of ecosystems and agriculture to the carbon budget in the event of global change. Agrometeorological information needs to be disseminated to users in time and space quite accurately, as agricultural activities are linked to the very local situation where the outputs of modern tools such as local area models, climate models, and dynamic crop simulation models are reduced to finer grid resolution and combined using GIS to extract practical suggestions. This chapter describes the recent applications of remote sensing in Agrometeorology.

5.1 Introduction

A Crop Simulation Model is a mathematical model which describes crop growth and development processes as a function of environment, soil conditions, and crop management. Simulation model is a schematic representation which works on set of underlying assumptions, equations and algorithms, closely replicating the behaviour of the agricultural systems. A crop growth simulation model predicts the harvestable yield. Apart from this final state of crop production, the model also provides a host of quantitative information about major processes involved in the various stages of crop development. The information covers each component of the crop such as leaves, stems, roots and harvestable products as they change over time, including the changes in soil moisture and nutrient status.

An increase in the population, demands an increase in agricultural production with available resources. Efficient management of available resources under varying weather conditions is important for increasing agricultural productivity. Besides that, the emphasis of agricultural production changes from quantity to quality and sustainability (Aggarwal et al., 2000). Solution of these new challenges lies in understanding the interaction of the numerous elements affecting the plant growth and generating a crop growth model. This extremely complicated information needs to be processed and interpreted on a spatial scale. Information technology which has unleashed new frontiers in data analysis and automation is the driving force behind this model generation. These powerful computer programmes simulate the crop growth or yield of crops under various management regimes and provide near real time information to help farmers to make strategic decision in the management of their crops.

Under normal weather situation, agriculture depends on timely occurrence of rainfall for crop management activities irrespective of different farming situations namely, irrigated and unirrigated agriculture. Changes in temperature and rainfall pattern together with frequent occurrence of extreme weather events are major anticipated threats from the climate change that occurs now around the world. This threat in long run, if not addressed properly, would affect food security of a country. Pratap Narain et al., (2000) observed an increase in moderate and severe drought occurrence numbers in the arid zone of India during last decade (1991-2000) as compared to the earlier decades of the last century. Similarly, Pasupalak (2008) reported daily maximum rainfall of 400.3 mm in the last decade against earlier record of 256.4 mm (1969–78) in a location at Odisha State. Further the inter- annual variation within the decade did increase and also the number of rainy days with very heavy rainfall > 125 mm also found increased in the location against the daily mean rainfall of 20 mm/day in India.

A day may be with heavy rainfall or with bright sunshine or windy or in combination of these. When heavy rainfall continues for more than a week with some system like cyclone, floods may be the result. Similarly, if dry spell continues during a cropping season for more than 15 days, drought would initiate in that region. This is again depending upon the nature of the soil water holding capacity and nature of soils, topography and green cover of that region. In between these two extremes, we have normal season, where we get normal seasonal rainfall during a cropping season. Hence like dress code, in agro-climatology, there are three weather codes, namely floods code, drought code and normal code. The jargon weather code was developed by Dr.M. S Swaminathan in India. Across the countries of the World, if these weather codes occur, the impact would be universal. The strength of adaptation capacity to maneuver these extreme events by the farming community rests with their past experience made for similar situations, financial support and also the technology options that are available from the scientific institutions.

7.1 Importance of Weather Forecast in Agriculture

In India, agriculture is in reality to be a “gamble activity” with the monsoon rain, that means the productivity and profit from agriculture depend upon the goodness of the season. If any malevolent weather situation that happens during a crop season, whether it is at the beginning of the crop season or at the mid of the crop season or at the terminal of the crop season or at the whole of the crop season, the productivity of the crops raised would be under stake. In practice the irrigated crop area is lesser than the area under unirrigated crop in India in any region except the regions where irrigation is routed through perennial rivers. Normally the production from unirrigated crop is 30 to 40 per cent of the same crop grown under irrigated condition in an environment in the same season.

In India, in a region or in a taluk, if the irrigated area is lesser than 30 per cent of total cultivable area, there is every opportunity for the occurrence of food shortage. That means assured production depends upon irrigation rather than managing the crops with seasonal rainfall alone. This clearly indicates that the higher probability of occurrence of crop production risks falls under rainfed/dry land situation. The crop production risk is also common to irrigated area like unirrigated crop but the intensity gets varied. In this context one example that happened in India can be quoted. During December- January of 1982, with the occurrence of heavy rain/snow as a result of prevalence of western disturbance weather system, the wheat crop stood for harvest at Punjab got damaged with a loss of 124 crore of rupees. If this was anticipated earlier through weather forecast development, (which is common in all developed countries) and communicated to the farmers in advance, then the yield loss would have been reduced by following some tactical decisions to be taken either by the farmers or by the concerned Government. At that time, India did not have medium range weather forecast system and hence Indian farmers met with greater losses.

8.1 Climate Change

Climate change is a broad term of global negative phenomena as created predominantly by burning of fossil fuels, which add heat-trapping gases to earth’s atmosphere. The over accumulation of greenhouse gases in the atmosphere lead to increased temperature and this is called as global warming. As a result, sea-level rise; ice mass loss in Greenland, Antarctica, Arctic and mountain glaciers worldwide; shifts in flowering/ plant blooming; and extreme weather events occur.

Livestock population meet the protein requirement of humans in addition to meeting from plants. The food chain starts from fodder crops to animals and from animals to humans. In human physiology, digestion of plant protein is much easier than animal protein, but however the digestion depends on climate (temperate climate, sub-tropical climate, tropical climate etc.,) wherein human kind live. Similar to crops, there is strong interaction between livestock and meteorological weather elements (temperature, relative humidity, wind etc.). But detailed study has not been published elaborately in scientific journals in the past. The weather elements have greater influence on livestock productivity in terms of milk, meat, skin, wool etc., pest and disease infestation and their housing needs. In this chapter how weather elements influence shed management, pest and disease problem and animals’ productivity and are discussed. In majority of the Veterinary and Animal Science University in India, they have one division on animal climatology, wherein both research and extension aspects are being attended. However, in depth research is the need of the present decade, since little works have been done in the past on animal climatology.

Irrespective of weather elements, the heat stress due to the combination of temperature and relative humidity plays important role in affecting the productivity of animals. There is a range of thermal conditions within which animals are able to maintain a relatively stable body temperature by means of behavioral and physiological means. Heat stress results from the animal’s inability to dissipate sufficient heat to maintain homeothermy (Sejian et al., 2017). High ambient temperature, relative humidity and radiant energy compromise the ability of the animals to dissipate heat. As a result, there is an increase in body temperature, which in turn initiates compensatory and adaptive mechanisms to re-establish homeothermy and homeostasis. Homeostasis refers to the tendency to maintain a balanced or constant internal state that is optimal for functioning. Animals have a specific balanced or normal body temperature. When there is a problem with the internal functioning of animal body, this temperature may increase, signaling imbalance. As a result, body attempts to solve the problem and restore homeostasis for normal body temperature. These readjustments generally referred as adaptations and this is essential for survival of the animals.

Astro-meteorology is considered as one of the branches of Astronomy along with Astrophysics, Astrobiology and Astrometry. Astronomy is the science that deals with the material universe beyond the earth’s atmosphere. It studies the nature and constitution of Celestial (heavenly) bodies and the laws which govern them including the effect they produce upon one another. It seeks to unravel the probable past history of heavenly bodies and their development. There exists a confusion between the branches of Astronomy viz., Astrophysics and Astro-meteorology with the term Astrology. Astrophysics uses principles and laws of physics to explain how Celestial bodies form and function or in other words it will help to ascertain the nature of the astronomical objects, rather than their positions or motions in space. However, the Astrology and Astro-meteorology are the subjects deal in future prediction and often considered as pseudo-science which uses position and movement of stars and planets for that purpose. Astrology links these to predict the human behaviour, while that of Astro-meteorology links the same to predict the future weather.

From ancient days, these predictions are based on one’s wisdom and knowledge in astronomy and often these astrologers are astronomers who keenly watch the stars and planets movement and guide their rulers and farmers with their guesstimates. Till date it is being lore, mainly passed to followers of this group and the methodology is not documented clearly and properly. There are many incidences of falsified predictions of astrology as reported by many reviewers elsewhere and we are not discussing the same here, owing to our interest in weather prediction i.e., astro-meteorology only. However, we have to recognize the works of the ancient astrologers who helped in developing the astronomical science.

Basically, there are two approaches in astrology viz., geocentric and heliocentric as used by the practitioner of astrology worldwide. As the name implies the Geocentric astrology is based on the calculation of planetary position as seen by the observer from the earth and thus earth is centre, while Heliocentric astrology bases its interpretation upon position within solar system with reference to the sun as centre. Though in true sense, the sun is the centre, the effect of motion as manifest on the earth is the basis of most astrological interpretation. Hence, vast majority of astrologers employs the geocentric calculations of the planetary positions for their predictions.

Analytical Chemistry

The science involving the determination of the constituents in terms of elements and compounds is called Analytical Chemistry. It is used to identify the substances found in a material and to quantify the exact amount of substances in them.

The basic principles involved in Analytical Chemistry are changes takes place in the substances by the process of combination, decomposition, replacement and double decomposition.

Laboratory analysis is an important part in any branch of chemistry and analytical chemistry in particular. To undertake the analysis, both apparatus and equipments are needed.

Standard solutions

Standard solutions are solutions of accurately known concentration

Different standard solutions are

Volumetric Analysis

Measurement of volume of reagents required for the completion of reactions

Also called titrimetry – most widely used techniques of chemical analysis

Rapid, accurate, convenient and inexpensive

Secondary standard solution

Solution of chemicals which lack one (or) all the properties for a primary standard

A solution standardised by titrating a primary standard

Less accurate than a primary standard

Indicator

A substance which indicates the end point on completion of the reaction.

Helps in the visual determination of the completion of titration.

Volumetry / Titrimetry

Process of determining the volume of solution of known concentration required to complete reaction with a solution of unknown concentration (test solution) by titration.

Gravimetric analysis

Techniques – analyte is determined by quantitative isolation of substance by precipitation and weighing the precipitate

Precipitation

An ionic phenomena wherein the product of the ionic concentrations of a substance in a solution exceeds the solubility product

Precipitate is often ignited before weighing to convert it into substance of definite chemical composition and chemical stability

Compound precipitated –– precipitated form

Example: Magnesium ammonium phosphate

I. Filtration

Filtration is a process of separation of precipitate from solution. Filtration is used to remove impurities from a solution (or) to isolate a solid.

Potentiometry

Potentiometry is based on measurement of potential of an electrode system

Principle

When a metal electrode is immersed in a solution containing its own ions, the metal atom pass into the solution in the form of metal ions and a potential difference is established between the metal and the solution. This potential is called as electrode potential.

Potential on an electrode depends on the ions present in solution and their concentration which can be determined by using electrochemical cells and expressed by Nernst equation

Colorimetry is the quantitative analysis of a coloured constituent. It is determined by measuring the relative amount of absorption of light passing through a solution of a constituent.

When a monochromatic light is passed through a homogeneous medium, a part of the incident light is absorbed and part of the light is reflected and part could be transmitted. This can be mathematically expressed as

Absorption and Emission

Absorption techniques – It measures the absorption of abundance of light due to electrons going to a higher energy level.

Emission techniques - It measures the intensity of light that is emitted as electrons return to the lower energy levels.

Chromatography is the set of laboratory techniques used for the separation of molecular mixtures by developing chromatograms. Chromatogram is a collection of different bands on the chromatographic column. The mixture is dissolved in a fluid called the “mobile phase”, which carries with it another material called the “stationary phase”. The various constituents of the mixture travel at different speeds, causing them to separate. Chroma (colour) and graph in (to write) contribute to the word chromatography, as coined by Mikhail Tswett (1903). Solute moves only when it is in stationary phase. In chromatography, the mobile phase flowing into the column is called eluent, the solution emerging from the column is elute, and the process by which solutes moves and separate is called elution.

This method employs the differences in absorbability of components of mixtures and the differences in the mobility rate. The molecules of a substance which interact strongly with the fixed phase will move slowly through the column whereas substances which do not interact strongly are carried through more rapidly. It is used to separate different substances having similar chemical properties.

Radiation Chemistry is a branch of nuclear chemistry that deals with the study of chemical effects of radiation on matter.

Radio activity is the process by which an atomic nucleus of an unstable atom loses energy by emitting ionizing radiations (a, b, g radiations). It may be of

Radiation emitted from the radioactive isotopes can be detected and quantified by using several equipments and the details are furnished below:

A. Radiation Detection Devices

1. Electroscope

The electroscope is a simple device comprised of a metal rod with two thin leaves attached to one end. If the electroscope is given a negative charge, the metal leaves will separate from each other. It is the characteristic that makes the electroscope useful as a detection device. A negatively charged electroscope will discharge when ions in the air remove electrons from it, and consequently, a positively charged electroscope will discharge when it takes electrons from the air around it. The rate of discharge of the electroscope is a measure of ions in the air and can be used as a basis of measurement and detection.

Stable isotopes are chemical isotopes that may or may not be radioactive,but if radioactive, have half-lives too long to be measured. These isotopes decay into stable products. Eg. ¹⁴C having 6protons and electrons with 8 neutrons.

Most elements of biological interest (including C, H, O, N, and S) have two or more stable isotopes. Among the stable isotopes, the most useful as biological tracers are the heavy isotopes of carbon and nitrogen.

1. Neutron activation analysis

This technique is used in qualitative and quantitative analysis. If an element present in a sample is to be identified by neutron activation analysis, the sample will be bombarded with slow neutrons or other charged particles and converted into radioisotope. It is one of the most sensitive and specific methods available for the determination of trace quantities of a wide range of elements. From the half life measurement, it is possible to identify the element from which the radioisotope has resulted. Also the quantity of element present in a given sample can be calculated by this technique.

Meteorology is derived from the Greek word meteoro which means above the earth’s surface; i.e., the atmosphere. The state of the atmosphere experienced at a given time, in any location on the surface of the earth is known as weather. Thus, meteorology is the scientific study of the atmosphere or the weather. It is a branch of physics dealing with atmosphere and it is often quoted as the ‘physics of the lower atmosphere’. The main focus of meteorology is to understand the weather processes and forecast the weather. Solar radiation, the air mass and moisture are the three key ingredients that make up weather. The exchange of heat, moisture and momentum between the earth’s surface and the atmosphere determines the characteristic of weather. The observable weather events are known as meteorological phenomena and are defined by a set of variables called weather elements. Atmospheric temperature, atmospheric pressure, humidity, precipitation, cloudiness, wind and visibility, etc. are examples of such weather elements. The weather elements are not separate entities. They are closely related with each other and are highly variable in nature. Meteorology explains and analyses the changes of these weather elements.

The major subdivisions of meteorology are dynamic meteorology (or atmospheric dynamics) and physical meteorology (or atmospheric physics). The dynamic meteorology is concerned with the analysis and interpretation of the three-dimensional, time-varying, macro scale motions and energy transformations in the atmosphere. The science of dynamic meteorology is meant to develop models based on the hydrodynamic and thermodynamic equations. The physical meteorology is concerned with the processes that alter the physical properties and the chemical composition of air parcels as they move through the atmosphere.

Atmosphere can be defined as the gaseous envelope surrounding the earth. It is retained by earth’s gravity. The atmosphere has a mass of about 5.15 × 10¹⁸ kg, three quarters of which is within about 11 km of the surface. The imaginary ‘Karman line’ lies at an altitude of 100 km above the earth’s sea level, and commonly represents the boundary between the earth’s atmosphere and outer space. The study of earth’s atmosphere and its processes is called atmospheric science or ‘aerology’.

Atmospheric pressure is the force per unit area exerted on a surface by the weight of air above that surface in the atmosphere of earth. The gas molecules of the atmosphere are pulled towards the earth by the force of gravity and hence exert a force on earth surface. Atmospheric pressure can be calculated as the summed weight of all gas molecules between a horizontal plane and top of the atmosphere and divided by the area of the plane. Low pressure areas have less atmospheric mass above their location, whereas high pressure areas have more atmospheric mass above their location.

Air in motion is called wind. Winds move moisture and heat around the world and also produce much of our weather. Winds are part of a global air circulation system that acts to balance temperature and pressure around the world. Any difference in temperature will always cause a difference in air pressure, and therefore, winds will blow. There are two types of movement in the atmosphere, horizontal movement and vertical movement. The term wind generally refers to the horizontal movement of air relative to the earth’s surface. Vertically moving air columns are called as currents. Upward and downward air currents are referred to as updrafts and downdrafts, respectively. Vertical motion in the atmosphere is of significance for the formation of clouds, precipitation and various types of storms. The horizontal differences in air pressure are far more variable than vertical changes and give rise to a wide range of air motions. Uneven distribution of pressure over the globe is balanced through the movement of winds. Winds also act as a means of transporting heat, moisture and other properties from one part of the earth to another.

The sun is a hot ball of glowing gases at the heart of the solar system. Its radiant energy is practically the only energy source to the earth. Very small and insignificant quantities of energy are available from other sources such as the interior of the earth, the moon, and other stars. Without the sun’s intense energy and heat, there would be no life on earth.

PROPERTIES OF SOLAR RADIATION

The mean distance of the sun from the earth, also known as one astronomical unit (1 AU), is approximately 1.496 × 10⁸ km, though the distance varies as the earth revolves round the sun in an elliptical orbit. At this average distance, light travels from the sun to earth in about 8 minutes and 19 seconds. The energy of the sunlight supports almost all life on earth by photosynthesis, and drives earth’s climate and weather. The minimum sun-earth distance is about 0.983 AU and the maximum is approximately 1.017 AU. The earth is at its closest point to the sun (perihelion) on around January 3 and at its farthest point (aphelion) on around July 4.

The sun makes up about 99.86% of the mass of the entire solar system. The visible disk or photosphere has a radius of 6.599 × 10⁵ km, and the solar mass is 1.989 × 10³⁰ kg. The sun is a completely gaseous body. The chemical composition (by mass) of the outer layers of sun is 71% hydrogen, 26.5% helium, and 2.5% heavier elements like oxygen, carbon, neon, and iron among others. Since the sun is not a solid body, different parts of the sun rotate at different rates. At the equator, the sun spins once about every 25 earth days, but at its poles the sun rotates once on its axis every 36 days.

Temperature is the physical property of an object that quantitatively expresses the hotness or coldness. Most of the weather parameters are dependent on temperature, directly or indirectly. It has important role to play in the development and growth of all living organisms in all stages of their growth. Atmosphere receives the heat energy from the sun and its temperature increases. Due to different amount of heat energy receipt at different places, the air temperatures at different places also vary. The variation in air temperature basically results into air motion, so as to equalize the energy content of the different regions of the earth. Thus, atmospheric temperature is one of the basic elements of weather and climate.

The temperature at a given location and time is affected by energy transfer processes including conduction, convection, advection and radiation. The controls of temperature include those factors that bring about spatial variations in temperature. The important factors that determine the temperature of a particular place on the earth’s surface are latitude, altitude, distribution of land and water, topography, ocean currents, prevailing wind, cloudiness, precipitation, nature of the surface, and turbulence.

Water is the only substance that exists in the atmosphere in all the three phases, i.e., solid, liquid and gas. The moisture on the earth's surface is in a constant phase change. The moisture content of the atmosphere is about 0.035% of all fresh water. The atmosphere receives its supply of moisture from the earth's surface through evaporation from oceans, lakes, rivers, damp soil, etc. and through transpiration from vegetation. Water vapour is the gaseous state of water and is invisible. The amount of water vapour present in the atmosphere is called atmospheric moisture or humidity. It is a measure of the amount of water vapour dissolved in the air, not including any liquid water or ice falling through the air.

Water vapour is constantly being cycled between the atmosphere and the earth's surface. The input rate (the rate at which water vapour enters the atmosphere from the ground through evaporation) and output rate (the rate at which water moves from the atmosphere to ground through precipitation) are equal. The average length of time that individual molecules of water remain in the atmosphere is called the residence time. It can be found by dividing the mass of the substance in the atmosphere (in kilograms) by the rate (in kg per year) at which the substance enters to and exists in the atmosphere. The total volume of atmospheric water vapour at any instance over the globe is about 14000 km³, which is 0.001% of the hydrosphere.

Although water vapour is lighter than air, the combination of higher temperatures and the ocean source tends to restrict it to the lower atmosphere. The decrease of water vapour with elevation is quite important in many meteorological processes. Infact, most of the water vapour is contained within the lower 5 km of the atmosphere (> 90%) and more than half is actually contained within the lowest 1.5 to 2 km. Less than 5 - 6% of the water is above 5 km, and less than 1% is in the stratosphere.

Precipitation is the deposition of atmospheric moisture on earth. All the water sources on the earth depend on precipitation only. Precipitation involves condensation, growth of hygroscopic nuclei, cooling of nuclei at different stages and their fall on to the earth's surface. If the cloud particles are too small and remain suspended in the sky, they may not fall on the earth. There may be several clouds but no precipitation. Under certain conditions, water particles formed tend to fall but do not reach the surface since they get evaporated on the way. Only when the cloud droplets or ice crystals grow to certain size and can no longer remain floating due to buoyancy of air, do they fall as precipitation.

FORMS OF PRECIPITATION

Precipitation form is the state that the moisture is in, i.e., liquid, freezing, or frozen (solid). Because atmospheric conditions vary greatly both geographically and seasonally, several different forms of precipitation are possible. All forms of precipitation are collectively termed hydrometeors. Hydrometeors have been classified into 50 specific types. Out of these precipitation forms, only rain (liquid form) and snow (solid form) make significant contribution to total precipitation. In many parts of the world, the term rainfall is used interchangeably with precipitation.

Clouds are the most important form of suspended water droplets caused by condensation. The World Meteorological Organisation defined cloud as a visible aggregate of minute particles of water or ice or both, in the free air. This aggregate may include larger particles of water or ice and particles such as those present in fumes, smoke or dust. The typical size of these water droplets and ice crystals range from less than 1 µm to 50 µm. When surrounded by billions of other droplets or crystals, they become visible as clouds. In the atmosphere sufficient moisture is required to allow condensation to take place. Then, moisture needs a suitable surface upon which it can condense. In free air, condensation begins on hygroscopic nuclei such as aerosols. These are microscopic particles and include dust, smoke, salts and chemical compounds. Nuclei range in size from 0.001 µm radius to over 10 µm. On an average, oceanic air contains one million condensation nuclei per litre and land air holds some 5 or 6 million. On hygroscopic particles such as sea salts, condensation can begin before the air is saturated. Supersaturation in clouds rarely exceeds one per cent. On average, clouds contain only four per cent of the total water in the atmosphere at any one time. Almost all clouds exist in the troposphere, although the tops of some severe thunderstorms occasionally extend to the stratosphere. Clouds move along with the wind and remain stationary in calm winds. They grow vertically and horizontally, depending on the temperature of the cloud and its ambient temperature. They may dissipate or precipitate. Under favourable atmospheric conditions, they burst and fall as rain. Clouds complete the following functions.

In the Indian sub-continent, monsoon is one of the oldest weather observations, an economically important weather pattern over June through September every year. Due to its effects on agriculture, flora and fauna, and other economic, social, and environmental effects, a monsoon is one of the most anticipated, followed and studied weather phenomena of the Indian subcontinent. The word 'monsoon' is derived from the Arabic word mawsim meaning season.

The term 'monsoon' is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea. India Meteorological Department defines it as the seasonal reversals of the wind direction along the shores of the Indian Ocean, especially in the Arabian Sea, that blow from the south-west during one half of the year and from the north-east during the other half. The definitions include major wind systems that change direction seasonally. The cyclic change of wind and rain can be separated into the summer monsoon period characterised by warm and humid south-west winds, and the winter monsoon period characterised by dry and cool north-east winds. In fact, monsoon systems are a major feature of the general circulation of the atmosphere in subtropical latitudes of most regions of the world.

There are various weather hazards that affect agricultural productions. These hazards affect crops and agricultural productivity negatively if they are not checked. Weather hazards include cyclones, droughts, floods, hailstorms, heatwaves and cold-waves. The hazard is distinguished from an extreme event and a disaster. An extreme event is simply an unusual event; it does not necessarily cause harm. A disaster is an event that does cause harm in significant amounts. Weather hazards are often called as natural hazards. The natural hazards become natural disasters when people’s lives and livelihoods are destroyed. Hydrologic hazards are the result of either excess or a severe lack of water, i.e., flood or drought. By issuing accurate forecasts and warnings in a form that is readily understood and by educating people about how to prepare against such hazards, before they become disasters, lives and property can be protected.

DROUGHT

Drought is a relative term used with reference to deficiency of rainfall when compared to normal rainfall of a given location. However, drought cannot be defined in terms of amount of rainfall or number of days without rain. Since ancient times droughts have had far-reaching effects on humankind by causing the failure of crops, decreasing natural vegetation, and depleting water supplies. Drought is different from other hazards; in that it develops slowly. It is a hazard that requires many months to emerge and that may persist for many months or years thereafter. This type of hazard is known as a ‘creeping’ hazard. Generally, this occurs when a region receives consistently below average precipitation.

The crops are very sensitive to climate. The crop production is dependent on climatic parameters like rainfall, light, temperature, relative humidity and carbon dioxide concentration. Each kind of cultivated crop plants has its own optimum growth requirements. Breeding and selection of new cultivars have allowed for a greater adaptability to less favourable growing conditions than was possible in the past, but the inherent climatic requirements of a specific kind of crop have not changed materially.

Weather and climate have also great influence on farm animal production. The environment in which an animal lives is referred to as its habitat. A habitat includes both biotic (living) and abiotic (non-living) components of the animals’ environment. Abiotic components of an animal’s environment include temperature, humidity, oxygen, wind, soil composition, day length and elevation. These potential environmental stressors can directly and adversely affect animal farming. The indirect consequences of weather include their impact on feed quality and availability.

Weather forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Forecasts based on temperature and precipitation is important to agriculture. Agricultural production is highly dependent on weather, climate and water availability, and is adversely affected by weather and climate related disasters. In many developing countries where rainfed agriculture is the norm, a good rainy season means good crop production, enhanced food security and a healthy economy. Farming in many parts of the world, especially in the arid and semiarid regions is risky, because climate is highly variable. A timely seasonal forecast of favourable conditions could permit farmers to adjust cropping patterns and input use in order to benefit fully from these conditions. Under rainfed conditions, even a less reliable, but earlier forecast may be more valuable than an accurate but late forecast.

In about 340 B.C., Aristotle described weather patterns in Meteorologica. Later, Theophrastus compiled a book on weather forecasting, called the Book of Signs. Ancient weather forecasting methods usually relied on observed patterns of events. This experience was accumulated over the generations to produce weather knowledge. However, not all of these predictions prove reliable, and many of them have since been found not to stand up to rigorous statistical testing. Two officers from of British Royal Navy, Francis Beaufort and Robert FitzRoy formed the basis for all of today’s weather forecasting knowledge by middle of 19th century. A terrible storm in 1859 inspired FitzRoy to develop charts to allow predictions to be made, which he called ‘forecasting the weather’, thus coining the term ‘weather forecast’. The ‘Weather Book’ which FitzRoy published in 1863 was far in advance of the scientific opinion of the time. By the early 20th century, scientists had begun to believe that weather forecasting could be predicted based on mathematical methods. Computers were first used to create surface analyses in 1992 and by 1998 digital imagery were used for satellite, radar and surface observations, encompassing nearly every factor of weather interpretation. Modern technology, particularly computers and weather satellites, and the availability of data provided by coordinated meteorological observing networks, has resulted in enormous improvements in the accuracy of weather forecasting.

The climate system is the highly complex system consisting of five major components; the atmosphere, the hydrosphere, the cryosphere, the land surface and the biosphere, and the interactions among them. The climate system evolves in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations and human-induced forcings such as the changing composition of the atmosphere and land-use.

The term ‘climate variability’ is often used to denote deviations of climatic statistics over a given period of time (e.g., a month, season or year) from the long-term statistics relating to the corresponding calendar period. In this sense, climate variability is measured by those deviations, which are usually termed anomalies.

‘Climate change’ refers to a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended period (typically decades or longer). Climate change may be due to natural internal processes or external forcings, or due to persistent anthropogenic changes in the composition of the atmosphere or in land use. The United Nation’s Framework Convention on Climate Change (UNFCCC) defines ‘climate change’ as ‘a change of climate behaviour which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods’. The UNFCCC thus makes a distinction between ‘climate change’ attributable to human activities altering the atmospheric composition, and ‘climate variability’ attributable to natural causes. Climate change is a long-term shift in weather conditions measured by changes in temperature, precipitation, wind, snow cover, and other indicators.

A key difference between climate variability and change is in persistence of ‘anomalous’ conditions. In other words, events that are used to be rare occur more frequently, or vice versa. Occasionally, an event or sequence of events occurs that has never been recorded before, such as the exceptional tsunami in the Indian Ocean in 2004 or hurricane season in the Atlantic in 2005. Yet even that could be a part of natural climate variability. If such a season does not recur within the next 30 years, by looking back it could be called as an exceptional year, but not a ‘climate change’. Only a persistent series of unusual events taken in the context of regional climate parameters can suggest that a potential change in climate has occurred.