Different Climatic Regions Of India Research Articles

Sustainable wastewater recovery system employing geothermal energy – Performance and feasibility study

In this study, a sustainable wastewater recovery system employing geothermal energy has been proposed. The efficiency of the suggested sustainable system has been simulated using heat transfer. Then, component-wise validation has been carried out with the existing data available in the literature wherever applicable and estimated an error of ± 8 %. The proposed sustainable system’s parametric and performance analyses have employed the developed vapor. From the parametric study, it is observed that hot spring temperatures have a significant influence on sustainable systems. Further, through performance investigation, it is understood that low dam/river/sea water temperatures and enhancing the water condenser effectiveness and flow rate ratio simultaneously improve the system performance. For different climatic regions of India, explored the feasible geothermal hotspots near dams/rivers/seawater and analyzed that among the hot and dry, hot and humid, composite and cold regions, the proposed sustainable system is best suitable at a composite region with a maximum possible water extraction/freshwater generation rate of 0.78 L/h for the given specifications and operating range. Moreover, it is assessed that hot spring temperature is the deciding factor for sustainable system performance in different climatic regions. Further, the current study can be used as a reference for understanding the phenomenon of potential geothermal hotspots for wastewater recovery in various climatic areas

Deciphering multi-temporal scale dynamics in the concentration, sources and processes of near surface ozone over different climatic regions of India.

This study aims to investigate the factors influencing seasonal and long-term (2003-2021) changes in the near surface ozone (850 hpa) concentrations over different climatic sub-regions of India. Detailed comparison of daily (2019-2021) near surface ozone values of ERA-5 and CAAQMS (Continuous Ambient Air Quality Monitoring Stations) ground-based measurements revealed that ERA-5 is temporally in phase with CAAQMS measurements falling indifferent climatic sub-regions of India. ERA-5 near surface ozone shows statistically significant long-term (2003-2021) positive trends [2-4 percent per decade (ppd)] over most of the climatic sub-regions, over Indo-Gangetic Planes (IGPs), Southern and Central India trends are particularly strong. Trends were also estimated for each season separately, which were largely positive (2-6 ppd) over Central and Southern India in the Autumn and Winter seasons. Extensive climatological analysis reveals that the reversal of winds in the Indian monsoonal system plays a vital role in such trend patterns across the Indian subcontinent. South-westerly winds from June through September presumably bring ozone deficit air of marine origin, thus causing a dilution effect while the North-easterly winds during late Autumn and early Winters plausibly bring ozone-rich air from the stratospheric-tropospheric efflux dominated Himalayan region. It allows near surface ozone enhancement over Central and Southern India. Seasonal Principal component analysis (PCA) revealed that precursor gases (CH4 and NO2) and climatic variables especially specific humidity (SH) are the primary drivers of near surface ozone variability in the Winter season, while in Spring, climatic variables like boundary layer height (BLH), temperature (T) and SH have a significant role. Principal component regression (PCR) reveals a long-term increase in near surface ozone levels mostly dominated by precursor concentration over IGPs and Southern sub-regions. Whereas, BLH, T and SH significantly explain near surface ozone trends over North-eastern and Coastal India.

Performance prediction of the Micro Solar Dome in different climatic regions of India from pilot-scale by Random Forest algorithm

As people living in remote areas still lack access to indoor lighting, the intervention of appropriate need-based innovations to improve basic indoor lighting facilities are essential. The present work discusses the development of a hybrid lighting device, Micro Solar Dome, that utilizes both the active and passive forms of solar energy to ensure sustainable lighting facilities for rural houses. The work elaborates the design, simulation, and pilot-scale installation of the device in 8 states in India. Based on the performance, a Principal Component Analysis was done, which indicated that more than 93% variation of the performance of the device was due to Global Horizontal Irradiance and Relative Humidity. A novel predictive model utilizing the Random Forest algorithm was developed for major Köppen climatic zones in India to determine the night-time performance of the device and validate the Principal Component Analysis results. As per the prediction, the average operation time of the device is about 3.5hrs at night, with the highest of 4.6 hrs in the Hot Desert Climate and the lowest of 2.4 hrs in the Humid Subtropical climate when 9 Köppen Zones are considered covering more than 95% of the geographic area of the country.

Short and Medium Range Forecast of Soil Moisture for the Different Climatic Regions of India Using Temporal Networks

Short and Medium Range Forecast of Soil Moisture for the Different Climatic Regions of India Using Temporal Networks

Spatio-temporal change in rainfall over five different climatic regions of India

AbstractThe present study deals with the estimation of dependences, spatio-temporal trends, change points, and stationarity in rainfall and rainy day series (1901–2013) for five (out of six) different climatic regions of India. Only one-fourth of the station rainfall and rainy day datasets exhibits long-term dependence on an annual and seasonal basis. The presence of lag-one serial correlation is prominent for almost all the climatic regions of India. The significant decreasing trend is found mainly for the stations of semi-arid and humid sub-tropical regions. The magnitude of rainfall is decreasing for most parts of the study area by 10% for annual and monsoon seasons. The change point is presented in a smaller number of stations. Non-stationary behaviour is observed for the rainy day series of semi-arid and humid sub-tropical regions, which may increase the temporal variability of rainfall over the same regions. The findings of this study could be very useful for the planning and management of water resources of different climatic regions of India.

Condition Assessment of Induced Draught Cooling Towers Located In Different Climatic Regions of India

Induced Draft Cooling Towers (IDCT) are an important industrial structures, which removes the heat absorbed in the circulating cooling water systems of thermal power plants. The cooling tower in general comprises of RCC members’ viz. Column, Beam, Slab, Wall, Louvers, Fanstack Shell etc. The process of operation is itself an important factor which affects the durability of members of IDCTs, due to which the RCC members of IDCT are subjected to varying exposure condition, some members are continuous under water, some are partially submerged, some have alternate drying & wetting and some are completely dry. Due to different exposure conditions of RCC members of these structures generally shows very contrasting states of distress i.e. varying from apparently un-distressed to highly distressed state. Apart from process of operation of IDCTs, the other important factors that affect the durability of these RCC structures are presence of Chloride in water being cooled & Chloride in concrete present during the construction and carbonation due to aging of concrete. The RCC structures were assessed by various Non-Destructive evaluation techniques and deterioration mechanisms were established. The present paper highlights the findings of condition assessment studies of selected IDCTs located in different climatic regions of India.

Study of thermal comfort in the residents of different climatic regions of India-Effect of the COVID-19 lockdown.

Thermal comfort standards are essential to ensure comfortable and enjoyable indoor conditions, and they also help in optimizing energy use. Thermal comfort studies, either climate chamber-based or field investigation, are conducted across the globe in order to ascertain the comfort limits as per the climatic and other adaptive features. However, very few studies are conducted when the occupants are subjected to a stressed condition, like the COVID-19 lockdown, which may not only have the health impacts but also have psychological impacts on the adaptation. In this paper, we present the results of the online study conducted regarding the status of thermal comfort during the COVID-19 lockdown in India. A total of 406 complete responses were collected from subjects located across 3 different climatic regions of India, that is, cold climate, composite climate, and hot and humid climate. Variations in clothing insulation, thermal sensation, and preference were noted across the different climatic regions. We also present the variation in opening of windows and running of fans with the variation in outdoor mean air temperature. The self-judged productivity, comfort, desire to go outdoors, and effectiveness of working from home were seen to vary with the increase in the days of lockdown.

Determining the cutoff of rainfall for Plasmodium falciparum malaria outbreaks in India

BackgroundMalaria outbreaks due to Plasmodium falciparum have been reported from various parts of India. Rainfall is considered as one of the major determinants for malaria outbreaks, however, an estimate of rainfall threshold for malaria is not known. Owing to the vast geographic area, the present study was planned to determine the amount of rainfall required for malaria outbreaks and the lag period between outbreak and rainfall in different Indian climatic regions. MethodsSimple statistical methods of overall mean and moving mean (case/mean ratio, CMR) were used to identify the districts with P. falciparum malaria outbreak due to rainfall and the amount of rainfall required for outbreaks. Of 120 districts reporting P. falciparum malaria outbreaks, 99 districts having substantially low number of cases (<100); <3 CMR in any year from 2009 to 2012 and districts having stable malaria transmission were excluded. Finally, analysis of outbreak month, lag period and the threshold of rainfall were determined in respect of 21 districts which represent different agro-climatic zones in the country. Whenever the moving mean of cases attained the value ≥3 in any month, that month was identified as P. falciparum malaria outbreak. The threshold amount of rainfall critical for malaria outbreak was calculated by the average mean of previous months (i.e., lag period). ResultsThe rainfall cutoff ranged from >70 to >600mm in different districts. The month of outbreak varied with the climatic zones viz. arid, semi-arid, humid and per-humid districts. In humid and per-humid districts, outbreaks occurred during monsoon period whereas in arid and semi-arid regions outbreaks occurred during the post monsoon period. The lag period varied from 1-3 months; long lag period was observed in arid, semi-arid region, while short lag period in humid and per-humid regions. ConclusionMalaria outbreaks can occur in post monsoon in arid and semi-arid region whereas in summer/monsoon in humid and per-humid regions. The lag period between rainfall and outbreak differs from one month with short lag (humid and per-humid) to long lag (arid and semi-arid). Based on the determined threshold of rainfall, the findings would be helpful in forewarning of imminent outbreak of malaria for the timely preparedness of malaria outbreaks not only in 21 studied districts, but also in several other districts of different climatic regions of India.

Changes in vegetation cover and soil intrinsic properties influence the soil bacterial community composition and diversity across different climatic regions of India

Soil microbial community in forest ecosystems plays a significant role in carbon and nutrient cycling. Very little is known about the effect of vegetation cover on soil bacterial community composition and diversity across different climatic regions of India. Soil was sampled from the plant cover dominated by seasonal herbs and grasses (PAS), Pinus roxburghii Sarg (PIN), Abies pindrow L. (FIR), Quercus incana Roxb (OKF), Mitragyna parvifolia Roxb (MIK); Acacia nilotica L. and Salvadora spp. (MIA) in three different climatic regions (humid, moist sub-humid and semi-arid) of India. The soil physical, chemical and biological properties such as sand (SAN), silt (SIL), clay (CLY), bulk density (SBD), wilting point (SWP), field capacity (SFC), saturated hydraulic conductivity (SHC), pH (SpH), organic carbon (SOC), nitrogen (SN), C:N ratio, available phosphorous (SAP) and total microbial activity (SMA) were determined. Illumina sequencing of specific 16S rRNA gene was applied to identify bacterial community composition in the soils under different vegetation cover. Results showed that the soil properties varied under different vegetation cover across the different climatic regions. SOC, SN, SMA were highest in the moist sub-humid region sites (PAS, PIN) followed by humid region (OKF, FIR) and semi-arid region (MIK, MIA) sites. However, the Chao 1 (species richness), Shannon and Simpson index (diversity) were highest in OKF, followed by MIK, FIR, MIA, PIN and PAS. The predominant bacterial phyla and genera in the soils under different vegetation cover were Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Planctomycetes, Verrucomicrobia, Thermotogae and Geobacter, Methylocapsa, Sphingomonas, Pseudomonas, Erysipelotrichaceae_incertae_sedis, Sporotomaculum, Amorphus, Helicobacter, Paenibacillus, Bauldia, Skermanella, Methylosinus, Singulisphaera, Marinobacter and Lamprocystis. We also found the exclusive OTUs abundance of some bacterial phyla and genera in the soils, which were not correlated with any one of the studied soil variables. In our analysis, we found only the Firmicutes, Verrucomicrobia and Bacteroidetes are linearly correlated (P < 0.05) with CLY, SWP and SpH. Likewise, bacterial genera Methylocapsa, Methylosinus and Amorphus were linearly correlated (P < 0.05) with SIL, SpH, C:N ratio and SAP. Our results suggested that the type of vegetation cover has a significant impact on changes in soil properties, controlling the soil bacterial community composition and diversity across different climatic regions of India. The soil bacterial community composition and diversity may serve as a potential ecological indicator with respect to land use and land cover change on biogeochemical cycling processes across different climatic regions of India.

Prevalence and molecular characterization of viruses causing diseases in Bombyx mori L. (Lepidoptera: Bombycidae) from different climatic regions of India

A number of viruses are known to cause the disease in mulberry silkworm, Bombyx mori L. and cause significant cocoon crop loss to the farmers. The study has been undertaken to assess the prevalence of silkworm viral diseases caused by B. Mori Nucleopolyhedrovirus (BmNPV), B. mori Infectious Flacherie Virus (BmIFV) and B. mori Densovirus1 (BmDNV1) through external symptoms and molecular characterization from different climatic regions of India. During the intensive exploratory surveys in 2017, silkworm larvae with typical symptoms of BmNPV, BmIFV and BmDNV1 were collected across seven provinces from North India [Kashmir (temperate), Jammu, Ghumarwin in Himachal Pradesh, Dehradun in Uttarakhand (subtropical) and South India [Karnataka, Andhra Pradesh and Tamil Nadu (tropical)]. Dissection of diseased specimens confirmed the presence of virus through anatomical changes viz, size, shape and colour of organs after disease attack. The viruses were isolated and identified through PCR amplification of highly conserved genes. The results reveal that BmNPV, BmIFV and BmDNV1 are evenly prevalent across India. The infection percentage of BmNPV, BmIFV and BmDNV1 in North India (11.41 ± 1.21, 7.81 ± 0.67 and 7.40 ± 0.61) was significantly higher than South India (1.61 ± 0.17, 1.52 ± 0.14 and 1.62 ± 0.14), respectively. The highest prevalence of these viruses was observed from subtropical followed by temperate and tropical climate. The knowledge of the prevalence of these viruses in India and their synergism with bacteria and influence of other possible factors is important for preventing cocoon crop losses caused by viral diseases in India.

Antiplasmodial potential and quantification of aloin and aloe-emodin in Aloe vera collected from different climatic regions of India

BackgroundIn this study, Aloe vera samples were collected from different climatic regions of India. Quantitative HPTLC (high performance thin layer chromatography) analysis of important anthraquinones aloin and aloe-emodin and antiplasmodial activity of crude aqueous extracts was done to estimate the effects of these constituents on antiplasmodial potential of the plant.MethodsHPTLC system equipped with a sample applicator Linomat V with CAMAG sample syringe, twin rough plate development chamber (20 x 10 cm), TLC Scanner 3 and integration software WINCATS 1.4.8 was used for analysis of aloin and aloe-emodin amount. The antiplasmodial activity of plant extracts was assessed against a chloroquine (CQ) sensitive strain of P. falciparum (MRC-2). Minimum Inhibitory Concentration (MIC) of aqueous extracts of selected samples was determined according to the World Health Organization (WHO) recommended method that was based on assessing the inhibition of schizont maturation in a 96-well microtitre plate. EC (effective concentration) values of different samples were observed to predict antiplasmodial potential of the plant in terms of their climatic zones.ResultsA maximum quantity of aloin and aloe-emodin i.e. 0.45 and 0.27 mg/g respectively was observed from the 12 samples of Aloe vera. The inhibited parasite growth with EC50 values ranging from 0.289 to 1056 μg/ml. The antiplasmodial EC50 value of positive control Chloroquine was observed 0.034 μg/ml and EC50 values showed by aloin and aloe-emodin was 67 μg/ml and 22 μg/ml respectively. A positive correlation was reported between aloin and aloe-emodin. Antiplasmodial activity was increased with increase in the concentration of aloin and aloe-emodin. The quantity of aloin and aloe-emodin was decreased with rise in temperature hence it was negatively correlated with temperature.ConclusionsThe extracts of Aloe vera collected from colder climatic regions showed good antiplasmodial activity and also showed the presence of higher amount of aloin and aloe-emodin in comparison to collected from warmer climatic sites. Study showed significant correlation between quantities of both the anthraquinones used as marker compounds and EC50 values of the different Aloe vera extracts. Although, both the anthraquinones showed less antiplasmodial potential in comparison to crude extracts of different Aloe vera samples. Diverse climatic factors affect the quantity of tested compounds and antiplasmodial potential of the plant in different Aloe vera samples.

Phytochemical Screening and Antibacterial Activity of Aloe Vera Collected from Different Climatic Regions of India

In this study Aloe vera accessions were collected from 12 states covering different climatic zones of India. The aqueous crude extracts were investigated for qualitative phytochemical diversity analysis, quantitative estimation of total phenol, alkaloid and flavonoid content and their antibacterial potential against ATCC (American Type Culture Collection) bacterial reference strains. Pearsoncoefficient correlation was used to correlate the quantitative estimation between tested bio-active compounds. Antibacterial potential was evaluated by agar well diffusion method against 9 bacterial reference ATCC strains. MIC (Minimum Inhibitory Concentration) values were calculated by microbroth dilution method. Different Aloe vera accessions showed the presence of alkaloids, glycosides, reducing sugar, phenolic compounds, flavonoids and tannins. Significant correlation was observed between alkaloids and phenols, and flavonoids and alkaloid contents. The correlation analysis also revealed the significant negative correlation between temperature and phenol (-0.803), and temperature and alkaloids (-0.779). Antibacterial activities measured in term of zone of inhibition against tested bacterial strains varied in different accessions of Aloe vera. Aqueous leaf extract of Aloe vera showed good antibacterial potential against both type of bacterial strains, gram positive S. aureus as well as gram negative E. coli and S. typhi. Highland and semi-arid zone accessions showed maximum phytochemical and antibacterial potential as compared to other Aloe vera accessions. Minimum MIC value of 1.2 mg/ml was shown by Highland samples against most of the reference strains. The results also concluded that phytochemical composition of Aloe vera is influenced by various environmental factors especially temperature and it is further correlated with antimicrobial potential of the plant.

Phytochemical Evaluation of Withanolide-A in Ashwagandha Roots from Different Climatic Regions of India

A b s t r a c t A r t i c l e I n f o Ashwagandha [Withania somnifera (L.) Dunal] is a highly valued medicinal plant in Ayurveda, used either singly or in combination with other herbs. Plants growing under different agro-climatic condition often show qualitative and quantitative variations in their phytoconstituents. In the GC-MS analysis, 24 bioactive phytochemical compounds were identified in roots and leaves of Withania somnifera. Present investigation deals with comparison of Ashwagandha plants (WsL, WsK, WsN and WsM) obtained from various regions (Lucknow, Karnataka, Nimuch and Mumbai) of India, for their withanolide-A contents using HPTLC. Methanolic root extracts of WsN showed maximum withanolide-A content (1.3%), WsK being close behind at 1.2% followed by WsM (0.7%); WsL showed minimum withanolide-A content at 0.4% only.

Chemical composition and acetylcholinesterase inhibitory activity of Artemisia maderaspatana essential oil

Context: To date, there are no reports to validate the Indian traditional and folklore claims of Artemisia maderaspatana L. (syn. Grangea maderaspatana L.) (Asteraceae) for the treatment of Alzheimer’s disease.Objective: The present study characterizes the volatile components (non-polar compounds) of A. maderaspatana and evaluates its acetylcholinesterase inhibition potential.Materials and methods: The essential oils (yield 0.06% v/w) were obtained from fresh aerial part of A. maderaspatana. The characterization of volatile components (non-polar compounds) was performed by GC–MS data and with those of reference compounds compiled in the spectral library of in-house database. The in vitro acetylcholinesterase (AChE) inhibition of the volatile organic constituents (VOC’s) of A. maderaspatana aerial part was evaluated in varying concentration ranges (0.70–44.75 µg/mL) with Ellman’s method.Results: The major components were α-humulene (46.3%), β-caryophyllene (9.3%), α-copaene (8.2%), β-myrcene (4.3%), Z(E)-α-farnesene (3.7%), and calarene (3.5%). Chemical variability among other Artemisia spp. from different climatic regions of India and countries namely Iran and France was observed. The experimental results showed that diverse volatile organic constituents of A. maderaspatana have significant acetylcholinesterase inhibitory activity (an IC50 value of 31.33 ± 1.03 µg/mL). This is the first report on the inhibition of acetylcholinesterase properties of essential oil of A. maderaspatana obtained from fresh aerial part.Conclusions: The present results indicate that essential oil of A. maderaspatana isolated from the northern region of India could inhibit AChE moderately. Therefore, the possibility of novel AChE inhibitors might exist in VOCs of this plant.

Insulating Materials for Energy Saving in Buildings

Insulation is considered one of the effective solutions to achieve energy savings in buidings. Better insulation having low thermal conductivity contributes significantly to new construction and retrofitting existing buildings. The Energy Conservation Building Code and National Building Code of India define the prescriptive and mandatory requirements for the U-factor and R-values for different climates but the way to achieve these values is left to the designers. As none of the walling and roofing assemblies in buildings fulfill the criteria for overall thermal transmittance, the study deals with determining the thermal conductivity of sustainable walling materials and prefab roofing technologies as well as insulating materials using Guarded Hot-Plate Apparatus. The MATLAB program is developed for computing the U-values and for predicting the desired retrofit insulation thicknesses to make different materials and roofing assembly combinations comply the Code requirements in different climatic regions of India. The results of the study are used for computing the performance with and without insulation using DesgnBuilder software for improving energy efficinecy of the buildings in composite climate in India.

Intercomparability of isotropic and anisotropic solar radiation models for different climatic zones of India

In present communication, a methodology is described to compute total radiation falling on inclined plane by employing the measured global and diffuse radiation data on horizontal surface of India. Five stations Jodhpur, Kolkata, Bangalore, New Delhi, and Srinagar representative of five different climatic zones—hot and dry, hot and humid, temperate, composite and cold, respectively are chosen for the study.The measured data of 15 years (from 1986 to 2000) are exploited and statistical analysis is carried out for the monthly mean daily data. Isotropic model of Liu and Jordan and anisotropic model of Hay are applied in the estimation of total radiation on tilted plane facing south with various slopes and an inter‐comparison between these two models is made to ensure their adaptability in different climatic regions of India. Four tilt angles viz. latitude, latitude +15°N, latitude‐15°N and 22.5°N are considered and both the models are used for computation of total radiation to test whether variation in tilt angles affect the reliability of models for any particular climatic zone.Furthermore, for realistic predictions, accuracy of isotropic and anisotropic models is tested through three statistical parameters and isotropic model is found fit for first four climatic zones of India while for cold region, performance of anisotropic seems better. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 925–932, 2014

Modifications to SCS-CN Method for Long-Term Hydrologic Simulation

The original soil conservation service curve number (SCS-CN) technique is primarily used to transform daily rainfall into surface runoff by assuming the proportionality between retention and surface runoff based on a parameter referred to as curve number (CN). The conventional method does not take into account the temporal and spatial variability of curve number. In this paper, an attempt has been made to modify the existing SCS-CN model in two ways by varying the CN using antecedent moisture condition (designated as Model I), and by using antecedent moisture amount (designated as Model II). The daily moisture storage is updated based on varying the curve number and other hydrologic abstractions. These two different models are constructed to compute streamflow components: Direct surface runoff, base flow, and hydrological abstractions. These methodologies were successfully applied to daily data of catchments of Cauvery, Narmada, Ganga, and Ulhas Rivers, lying in different climatic regions of India, and the results were analyzed. Application of Model I to Hemavati (a tributary of River Cauvery, Karnataka State) data yielded maximum efficiency of 84% in calibration, and minimum efficiency of 54% with Ramganga (a tributary of River Ganga, Uttaranchal State) data, whereas Model II showed maximum efficiency of 85% in Hemavati catchment and minimum efficiency of 64% in Kalu catchment (a tributary of River Ulhas, Maharashtra State). Model II performed better than Model I on all four catchments. It is found that the proposed models reasonably simulate the catchment response and these SCS-CN-based models are applicable to complex natured watersheds.

Long-term hydrologic simulation using storage and source area concepts

A daily rainfall–runoff model of the lumped, storage- and source area-based concepts incorporating in runoff generation the processes of initial abstraction, evaporation transpiration, infiltration, drainage, percolation, deep seepage, source area runoff, throughflow and base flow, is proposed. It is calibrated and validated for data of five catchments falling in different climatic regions of India. The model is found to perform well on all the watersheds except one, exhibiting minimum runoff coefficient. It performs better on the high runoff producing watersheds than on the low ones. In addition, the dormancy/dominancy of various processes in various watersheds is identified, and the expansion/contraction of the source area explained. The deep percolation is found to affect significantly the runoff generation in all the considered watersheds. Since the models of Moore et al. (1983) and Putty and Prasad (1993) do not account for this process, the proposed model forms advancement over these models. Copyright © 2005 John Wiley & Sons, Ltd.

Water production functions for wheat under different environmental conditions

Water production functions have been developed in numerous forms; however, their transferability to widely different soils and climatic conditions is still a debatable subject. A study was conducted to evaluate the performance of existing evapotranspiration-yield functions for wheat with regard to their applicability and transferability under different environmental conditions in India. The functions were verified with data from field experiments conducted at a number of research stations located in different climatic regions of India. Depending on the nature of data input the functions were grouped into seasonal and growth stage functions. All functions were found to be statistically acceptable with regard to fitting available data. However, regression coefficients, i.e., yield response sensitivity factors varied in magnitude with the location of experiment even for the same wheat variety, which implies that the existing functions are site specific. Further the yield response sensitivity factor for the seasonal function was found to be dependent on site climatic and soil variables.