Long-term (2001–2020) trend analysis of temperature and rainfall and drought characteristics by in situ measurements at a tropical semi-arid station from southern peninsular India Lokeswara Reddy Thotli, Balakrishnaiah Gugamsetty, Raja Obul Reddy Kalluri, Chakradhar Rao Tandule, Rama Gopal Kotalo, Bhavyasree Akkiraju, Siva Sankara Reddy Lingala International Journal of Climatology, 2022 With the effects of climate change prevailing worldwide, it is essential to understand the long‐term rainfall and temperature trends at regional scales to plan for adaptation strategies. Investigating the temporal dynamics of meteorological variables in climate‐induced changes, particularly in rain‐fed agriculture countries such as India, is needful. The present study focused on the temporal variation of rainfall and temperature trends to analyse the drought characteristics over the past 20 years (2001–2020) using ground‐based Automatic Weather Station (AWS) data at a semi‐arid station Anantapur in southern peninsular India. The seasonal maximum mean temperature (Tmean) was observed in summer (32.20 ± 1.36°C), followed by the monsoon (29.08 ± 1.02°C), postmonsoon (26.45 ± 2.44°C), and winter (25.45 ± 1.01°C) during the study period. The Mann–Kendall trend test result showed the decreasing trend in seasonal mean temperature during the drying period (winter [−0.069°C·year−1] and summer [−0.081°C·year−1]) and increasing trend in the wetting period (monsoon [0.012°C·year−1] and postmonsoon [0.034°C·year−1]). On the other hand, the seasonal rainfall decreases in the postmonsoon (−2.276 mm·year−1) while increasing in winter (0.5 mm·year−1), summer (2.137 mm·year−1), and monsoon (6.901 mm·year−1) seasons. The annual trends of minimum, maximum, and mean monthly temperatures decrease at the rate of −0.121, −0.123, and −0.022°C·year−1, respectively, while the rainfall increases at the rate of 8.979 mm·year−1. Furthermore, the temporal evolution of meteorological drought characteristics was estimated with the help of the standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI) on multiple timescales ranging from 1 to 24 months on a monthly basis during the study period. The 24‐month SPI values showed that 1 “severely dry” and the 29 “moderately dry” long‐term drought events were observed. From 24‐month SPEI, a total of 15 “severely dry” and 20 “moderately dry” long‐term droughts were observed during the study period. The severely dry years were observed in 2002 and 2003, while the wettest periods were 2007 and 2010. Both indices are identified as more severe dry periods from 2002 to 2006 and 2013 to 2017 than rest periods. Also, a significant decreasing tendency of droughts was observed in both indices. The SPI values are compared with El Niño–Southern Oscillation (ENSO) and normalized difference vegetation index (NDVI) and found that the SPI versus ENSO index negatively correlates with the coefficient of −0.58 significantly, while the SPI versus NDVI correlation is insignificant. The study region converted to wetter conditions during the last 20 years.
On the net primary productivity over the Arabian Sea due to the reduction in mineral dust deposition Chakradhar Rao Tandule, Mukunda M. Gogoi, Rama Gopal Kotalo, S. Suresh Babu Scientific Reports, 2022 The dust plume tracks from the Middle East and Eastern Africa to the Indian subcontinent have an impact on the atmospheric and ocean biogeochemistry of the Arabian Sea (AS). Here, we present the impact of dust on net primary productivity (NPP) over the AS using satellite-based observation and model simulation. Seasonal episodes and long-term trends in dust optical depth (DOD), dust mass flux (DMF) and dust deposition flux (DDF) from 2007 to 2020 are quantified. Nearly 32% of the total dust is advected to the AS during transport (maximum in JJA; DMF ~ 33.1 Tg year−1 ~ 56% of annual and DDF ~ 5.5 Tg year−1 ~ 63% of annual). Over the last one and half decades, there has been a statistically significant decreasing trend in DOD, associated with precipitation, enhanced vegetation index and surface soil moisture over the landmasses in the proximity of the AS. Similarly, the depletion in DDF suppresses the NPP over different regions of the AS, especially over the central AS, where the oceanic supply of nutrients is limited.
Diurnal, seasonal, and vertical distribution of carbon monoxide levels and their potential sources over a semi-arid region, India , Elijabetthamma Busa, Balakrishnaiah Gugamsetty, , Raja Obul Reddy Kalluri, , Rama Gopal Kotalo, , Chakradhar Rao Tandule, , Lokeswara Reddy Thotli, , Manjunatha Chakala, , Surya Nagi Reddy Palle, and Atmosfera, 2022 The present study focuses on the investigation of both near-surface and vertical variability of carbon monoxide (CO) concentrations and their potential sources obtained from both in situ and satellite Measurements of Pollution in the Troposphere (MOPITT) over a semiarid region (Anantapur, India) from January 2016 to December 2017. The diurnal variation of CO shows sharp morning (07:00-09:00 LT) and evening (07:00-09:00 LT) peaks associated to local anthropogenic activities as well as the impact of the mixed layer height, and low concentrations during daytime (12:00-15:00 LT). The low levels during afternoon hours may be due to the increase of the mixed layer height and the decrease of anthropogenic sources. The seasonal mean CO showed no obvious variation, with highest levels observed in winter (329 ± 52 ppbv), followed by the pre-monsoon (327 ± 57 ppbv), post-monsoon (234 ± 36 ppbv) and monsoon (192 ± 22 ppbv). The high levels of CO during the winter are attributed to increased emissions from anthropogenic sources and a shallow mixed layer height. The vertical distribution of CO showed secondary peaks at high-pressure levels (300-200 hPa) during winter, pre-monsoon, and post-monsoon, which indicates CO transport from different source regions. These findings are reasonably confirmed through the air mass Concentrated Weighted Trajectory (CWT) analysis obtained from the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. This study suggests that except for the monsoon, air masses transported from Indo-Gangetic Basin region also contribute to the enhancement of CO concentrations at the receptor site
The impact of lockdown on ebc mass concentration over a semi-arid region in southern india: Ground observation and model simulations Surya Nagi Reddy Palle, Chakradhar Rao Tandule, Raja Obul Reddy Kalluri, Balakrishnaiah Gugamsetty, Rama Gopal Kotalo, Lokeswara Reddy Thotli, Bhavyasree Akkiraju, Siva Sankara Reddy Lingala Aerosol and Air Quality Research, 2021 In the present study, we focused on the impact of lockdown on black carbon (eBC) mass concentrations and their associated radiative implications from 01st March to 30th June 2020, over a semi-arid station, i.e., in the district of Anantapur in Southern India. The mean eBC mass concentration was observed before lockdown (01st-24th March 2020) and during the lockdown (25th March to 30th June 2020) period and was about 1.74 ± 0.36 and 1.11 ± 0.14 µg m-3, respectively. The sharp decrease (~35%) of eBC mass concentration observed during the lockdown (LD) period as compared with before lockdown (BLD) period, was mainly due to the reduction of anthropogenic activities and meteorology. Furthermore, during the entire LD period, the net composite forcing at the top of the atmosphere (TOA) and at the surface (SUR) varied from -4.52 to -6.19 Wm–2 and -22.91 to -29.35 Wm–2, respectively, whereas the net forcing in the atmosphere (ATM) varied from 17.27 to 23.16 Wm–2. Interestingly, the amount of energy trapped in the atmosphere due to eBC is 11.19 Wm–2 before LD and 8.56 Wm–2 during LD. It is concluded that eBC contributes almost 43–50% to the composite forcing. As a result, the eBC atmospheric heating rate decreased significantly (25%) when compared to before lockdown days to lockdown days.
Retrieval of Aerosol Optical Depth from INSAT-3DR for Accurate Geostationary Monitoring of Regional and Temporal Aerosol Dynamics CR Tandule, MM Gogoi, SS Gouda, SS Babu Atmospheric Environment, 121730 , 2025 2025
Speciated and spectral aerosol direct radiative forcing over the northern Indian Ocean during the south Asian outflow in the Winter 2018 ICARB experiment MM Gogoi, VS Nair, CR Tandule, P Hegde, SK Kompalli, SS Babu Atmospheric Environment, 121457 , 2025 2025
Improved cloud screening of OceanSat-3 OCM-3 satellite imagery using machine learning algorithm CR Tandule, MM Gogoi, SS Babu Remote Sensing Applications: Society and Environment 37, 101481 , 2025 2025 Citations: 2
The effect of local pollution and transport dust on near surface aerosol properties over a semi-arid station from ground and satellite observations B Akkiraju, CR Tandule, B Gugamsetty, ROR Kalluri, LR Thotli, RG Kotalo, ... Air Quality, Atmosphere & Health 17 (3), 541-558 , 2024 2024 Citations: 1
Long‐term (2001–2020) trend analysis of temperature and rainfall and drought characteristics by in situ measurements at a tropical semi‐arid station from southern peninsular India LR Thotli, B Gugamsetty, ROR Kalluri, CR Tandule, RG Kotalo, B Akkiraju, ... International Journal of Climatology 42 (16), 8928-8949 , 2022 2022 Citations: 12
On the net primary productivity over the Arabian Sea due to the reduction in mineral dust deposition CR Tandule, MM Gogoi, RG Kotalo, SS Babu Scientific Reports 12 (1), 7761 , 2022 2022 Citations: 24
Diurnal, seasonal, and vertical distribution of carbon monoxide levels and their potential sources over a semi-arid region, India E Busa, B Gugamsetty, ROR Kalluri, RG Kotalo, CR Tandule, LR Thotli, ... Atmósfera 35 (1), 165-178 , 2022 2022 Citations: 6
Response of ambient BC concentration across the Indian region to the nation-wide lockdown MM Gogoi, SS Babu, BS Arun, KK Moorthy, A Ajay, P Ajay, A Suryavanshi, ... Current Science 120 (2), 341-351 , 2021 2021 Citations: 47
The Impact of Lockdown on eBC Mass Concentration over a Semi-arid Region in Southern India: Ground Observation and Model Simulations CR Tandule, SNR Palle, ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, ... Aerosol and Air Quality Research 21, 210101 , 2021 2021 Citations: 12
Impact of aerosols on surface ozone during COVID-19 pandemic in southern India: A multi-instrumental approach from ground and satellite observations, and model simulations ROR Kalluri, B Gugamsetty, CR Tandule, RG Kotalo, LR Thotli, RR Rajuru, ... Journal of Atmospheric and Solar-Terrestrial Physics 212, 105491 , 2021 2021 Citations: 16
Diurnal, seasonal and vertical distribution of carbon monoxide levels and their potential sources over a semi-arid region, India RG Kotalo, E Busa, B Gugamsetty, ROR Kalluri, CR Tandule, LR Thotli, ... Atmósfera , 2020 2020
Long-term analysis of atmospheric composite aerosol and black carbon radiative forcing over a semi-arid region in southern India: model results and ground measurement ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, CR Tandule, B Akkiraju TIDEE: TERI Information Digest on Energy and Environment 19 (4), 489-490 , 2020 2020
Perturbations of atmospheric surface layer characteristics during the annular solar eclipse on 26 December 2019 over a semi-arid region Anantapur in southern India L Reddy, G Balakrishnaiah Journal of Atmospheric and Solar-Terrestrial Physics 211, 105467 , 2020 2020 Citations: 9
Long-term (2008–2017) analysis of atmospheric composite aerosol and black carbon radiative forcing over a semi-arid region in southern India: Model results and ground measurement ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, CR Tandule, B Akkiraju Atmospheric Environment 240, 117840 , 2020 2020 Citations: 26
Decadal climatology of the spatial and vertical distributions of tropospheric aerosol over the Arabian Sea based on satellite observations CR Tandule, ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, RR Rajuru, ... Int. J. Climatol 40 (10), 4676-4689 , 2020 2020 Citations: 21
Chemical characterization and source identification of particulate matter at Ballari (15.15 N, 76.93 E), Karnataka over Southern Indian region V Shalini, K Narasimhulu, KRO Reddy, G Balakrishnaiah, KR Gopal, ... Journal of Atmospheric and Solar-Terrestrial Physics 200, 105192 , 2020 2020 Citations: 11
Spatial gradient of aerosol mass concentrations and size distributions over southeastern Arabian Sea and equatorial Indian Ocean during ICARB-2018 MM Gogoi, CR Tandule, SK Kompalli, VS Nair, KR Gopal, SS Babu Atmospheric Environment 213, 727-738 , 2019 2019 Citations: 26
Analysis of exceedance in the daily PM10 mass concentrations over five mega south Indian cities RRR C. Manjunatha, T. Chakradhar Rao, G. Balakrishnaiah, K. Rama Gopal, T ... International Journal of Research in Advent Technology 7 (4), 699 – 710 , 2019 2019
Investigation of black carbon aerosols and their characteristics over tropical urban and semi-arid rural environments in peninsular India SN Hussain, TC Rao, G Balakrishnaiah, KR Gopal, KRO Reddy, ... Journal of Atmospheric and Solar-Terrestrial Physics 167, 48-57 , 2018 2018 Citations: 27
Observations of trace gases, photolysis rate coefficients and model simulations over semi-arid region, India AP Lingaswamy, SM Arafath, G Balakrishnaiah, KR Gopal, NSK Reddy, ... Atmospheric Environment 158, 246-258 , 2017 2017 Citations: 13
MOST CITED SCHOLAR PUBLICATIONS
Seasonal variation of near surface black carbon and satellite derived vertical distribution of aerosols over a semi-arid station in India ROR Kalluri, B Gugamsetty, RG Kotalo, SKR Nagireddy, CR Tandule, ... Atmospheric Research 184, 77-87 , 2017 2017 Citations: 48
Response of ambient BC concentration across the Indian region to the nation-wide lockdown MM Gogoi, SS Babu, BS Arun, KK Moorthy, A Ajay, P Ajay, A Suryavanshi, ... Current Science 120 (2), 341-351 , 2021 2021 Citations: 47
Direct radiative forcing properties of atmospheric aerosols over semi-arid region, Anantapur in India ROR Kalluri, B Gugamsetty, RG Kotalo, SKR Nagireddy, CR Tandule, ... Science of the Total Environment 566, 1002-1013 , 2016 2016 Citations: 47
Regional trends of aerosol optical depth and their impact on cloud properties over Southern India using MODIS data KR Gopal, KRO Reddy, G Balakrishnaiah, SMD Arafath, NSK Reddy, ... Journal of Atmospheric and Solar-Terrestrial Physics 146, 38-48 , 2016 2016 Citations: 35
Investigation of black carbon aerosols and their characteristics over tropical urban and semi-arid rural environments in peninsular India SN Hussain, TC Rao, G Balakrishnaiah, KR Gopal, KRO Reddy, ... Journal of Atmospheric and Solar-Terrestrial Physics 167, 48-57 , 2018 2018 Citations: 27
Long-term (2008–2017) analysis of atmospheric composite aerosol and black carbon radiative forcing over a semi-arid region in southern India: Model results and ground measurement ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, CR Tandule, B Akkiraju Atmospheric Environment 240, 117840 , 2020 2020 Citations: 26
Spatial gradient of aerosol mass concentrations and size distributions over southeastern Arabian Sea and equatorial Indian Ocean during ICARB-2018 MM Gogoi, CR Tandule, SK Kompalli, VS Nair, KR Gopal, SS Babu Atmospheric Environment 213, 727-738 , 2019 2019 Citations: 26
On the net primary productivity over the Arabian Sea due to the reduction in mineral dust deposition CR Tandule, MM Gogoi, RG Kotalo, SS Babu Scientific Reports 12 (1), 7761 , 2022 2022 Citations: 24
Long term (2007–2013) observations of columnar aerosol optical properties and retrieved size distributions over Anantapur, India using multi wavelength solar radiometer KRO Reddy, G Balakrishnaiah, KR Gopal, NSK Reddy, TC Rao, ... Atmospheric Environment 142, 238-250 , 2016 2016 Citations: 22
Decadal climatology of the spatial and vertical distributions of tropospheric aerosol over the Arabian Sea based on satellite observations CR Tandule, ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, RR Rajuru, ... Int. J. Climatol 40 (10), 4676-4689 , 2020 2020 Citations: 21
Measurements of scattering and absorption properties of surface aerosols at a semi-arid site, Anantapur KR Gopal, G Balakrishnaiah, SM Arafath, KRO Reddy, NSK Reddy, ... Atmospheric Research 183, 84-93 , 2017 2017 Citations: 21
Impact of aerosols on surface ozone during COVID-19 pandemic in southern India: A multi-instrumental approach from ground and satellite observations, and model simulations ROR Kalluri, B Gugamsetty, CR Tandule, RG Kotalo, LR Thotli, RR Rajuru, ... Journal of Atmospheric and Solar-Terrestrial Physics 212, 105491 , 2021 2021 Citations: 16
Observations of trace gases, photolysis rate coefficients and model simulations over semi-arid region, India AP Lingaswamy, SM Arafath, G Balakrishnaiah, KR Gopal, NSK Reddy, ... Atmospheric Environment 158, 246-258 , 2017 2017 Citations: 13
Long‐term (2001–2020) trend analysis of temperature and rainfall and drought characteristics by in situ measurements at a tropical semi‐arid station from southern peninsular India LR Thotli, B Gugamsetty, ROR Kalluri, CR Tandule, RG Kotalo, B Akkiraju, ... International Journal of Climatology 42 (16), 8928-8949 , 2022 2022 Citations: 12
The Impact of Lockdown on eBC Mass Concentration over a Semi-arid Region in Southern India: Ground Observation and Model Simulations CR Tandule, SNR Palle, ROR Kalluri, B Gugamsetty, RG Kotalo, LR Thotli, ... Aerosol and Air Quality Research 21, 210101 , 2021 2021 Citations: 12
Chemical characterization and source identification of particulate matter at Ballari (15.15 N, 76.93 E), Karnataka over Southern Indian region V Shalini, K Narasimhulu, KRO Reddy, G Balakrishnaiah, KR Gopal, ... Journal of Atmospheric and Solar-Terrestrial Physics 200, 105192 , 2020 2020 Citations: 11
Perturbations of atmospheric surface layer characteristics during the annular solar eclipse on 26 December 2019 over a semi-arid region Anantapur in southern India L Reddy, G Balakrishnaiah Journal of Atmospheric and Solar-Terrestrial Physics 211, 105467 , 2020 2020 Citations: 9
Diurnal, seasonal, and vertical distribution of carbon monoxide levels and their potential sources over a semi-arid region, India E Busa, B Gugamsetty, ROR Kalluri, RG Kotalo, CR Tandule, LR Thotli, ... Atmósfera 35 (1), 165-178 , 2022 2022 Citations: 6
Evaluation of clearness and diffuse index at a semi-arid station (Anantapur) using estimated global and diffuse solar radiation GP Rama, KS Pavan, G Balakrishnaiah, ORK Raja, S Md Arafath, ... International Journal of Advanced Earth Science and Engineering 5, 347-363 , 2016 2016 Citations: 4
Improved cloud screening of OceanSat-3 OCM-3 satellite imagery using machine learning algorithm CR Tandule, MM Gogoi, SS Babu Remote Sensing Applications: Society and Environment 37, 101481 , 2025 2025 Citations: 2
