Jayanarayanan Kuttippurath

Indian Institute of Technology Kharagpur | IIT KGP · Centre of Oceans, Rivers, Atmosphere and Land Sciences

Methane (CH 4) is a prominent Greenhouse Gas (GHG) and its global atmospheric concentration has increased significantly since the year 2007. Anthropogenic CH 4 emissions are projected to be 9390 million metric tonnes by 2020. Here, we present the long-term changes in atmospheric methane over India and suggest possible alternatives to reduce soil em...

A comprehensive analysis of the temporal evolution of tropospheric ozone in Antarctica using more than 25 years of surface ozone and ozonesonde measurements reveals significant changes in tropospheric ozone there. It shows a positive trend in ozone at the surface and lower and mid-troposphere, but a negative trend in the upper troposphere. We also...

Continuous use of chemical fertilizers is detrimental to soil health and crop productivity. Therefore, we need to recycle the agroresidues in the valorized form (e.g., biochar or compost) to improve soil quality while maintaining crop yield. This study compares different nutrient management practices using varied dose combinations of biochar/compos...

Severe vortex-wide ozone loss in the Arctic would expose both ecosystems and several millions of people to unhealthy ultraviolet radiation. Adding to these worries, and extreme events as the harbingers of climate change, exceptionally low ozone with column values below 220 DU occurred over the Arctic in March and April 2020. Sporadic occurrences of...

The passive ozone method is used to estimate ozone loss from ground-based measurements in the Antarctic. A sensitivity study shows that the O₃ loss can be estimated within an accuracy of ~4%. The method is then applied to the observations from Amundsen-Scott/South Pole, Arrival Heights, Belgrano, Concordia, Dumont d'Urville, Faraday, Hal...

This study investigates long-term changes in phytoplankton size classes (PSC) in the Arabian Sea (AS) using 12 years (2010–2021) of remote sensing reflectance (Rrs) data from the Moderate Resolution Imaging...

Indian summer monsoon (ISM) is the prominent global monsoon system, which occur annually from June to September and impacts the lives of over a quarter of the world's population. Studies show that global warming is one of the key reasons for the extreme events such as droughts and floods, and that also alter regional dynamics of ISM. Consequently,...

There is a significant increase in ozone at the surface and troposphere due to growing population, industrialisation and urbanisation. The initiation of National Clean Air Programme (NCAP) in 2019 marked a turning point in addressing air pollution in Indian cities. The Central Pollution Control Board (CPCB) ground-based measurements show a reductio...

Flash drought events can be characterised by the quick depletion of crop root zone soil moisture (rapid intensification) and hence can be termed as agricultural flash droughts. These events can have devastating impacts, such as increasing the risk of agricultural yield loss, heatwaves and increased wildfire risk, which further have cascading impact...

Soil moisture (SM) interconnects various components of the Earth system and drives the land–atmosphere feedbacks and food production. However, around 40% of global vegetated land experiences SM drying. India is one of the global hotspots of land–atmosphere interactions and an extensively agrarian economy, but underexplored in terms of SM dynamics a...

Humidity or the amount of moisture in the air is a crucial component of the hydrological cycle and it affects the weather and climate of a region. The Indian National Satellite (INSAT)-3D (January 2014–May 2017) and INSAT-3DR (January 2017–December 2021) are the geostationary weather monitoring space systems of India, which use advanced Imager and...

The Thar is the most densely populated desert in the world, which supports diverse ecosystems and human endeavours such as agriculture and socioeconomic activities. Water demand and supply in the Thar play an essential role in regulating the socioeconomic activities of the region. Inland water and precipitation aid the movement of water in the Thar...

The Third Pole (TP) is the world’s largest highland and has one of the biggest reservoirs of glacier ice mass and snow cover on the Earth. Three major Asian rivers (the Indus, Ganga and Brahmaputra) are nourished by the melting of glaciers and snow in Central Himalaya, which are inevitable for the socioeconomic sustainability and water security of...

We assess the spatio-temporal changes in global atmospheric nitrogen dioxide (NO₂) in its hotspots and 3000 cities with respect to past and current vehicular policies for the period 2002–2019. The quantile-quantile (Q-Q) adjustment method is applied to merge the NO₂ measurements from different satellites to make the long-term data (2002–2019) for t...

Sulphur dioxide (SO2) is a hazardous air pollutant, which is mostly emitted from burning of fossil fuels, and has an adverse impact on the human health and ecosystem functioning. The COVID-19 natural anthropause (lockdown) provides a great opportunity to understand the changes in SO2 pollution across the globe, as there was a temporary standstill f...

Stratospheric ozone is an important constituent of the atmosphere. Significant changes in its concentrations have great consequences for the environment in general and for ecosystems in particular. Here, we analyse ground-based, ozonesonde and satellite ozone measurements to examine the ozone depletion and the spatiotemporal trends in ozone in the...

The development of catastrophic mesoscale convective systems in the atmosphere, such as thunderstorms, is caused by several factors, the most important of which is moisture in the lower troposphere and then the instability and lifting of air parcels. In pre-monsoon, northeast and adjoining eastern India are susceptible to thunderstorms. Herein, we...

Climate change, anthropogenic activities and frequent extreme events have caused significant changes in vegetation cover, photosynthetic activity, and productivity around the world in recent decades. At the same time, in the global warming scenario around 40% of land is experiencing moisture stress. India, is the second largest contributor to globa...

The Earth’s surface temperatures have increased significantly since the beginning of industrialisation. The substantial emissions of greenhouse gases have played a role in global warming and the ongoing climate change, with projections indicating continued trends. This study explores the long-term surface temperature trends in India from 1980 to 20...

Moisture stress has increased substantially across the globe with significant impact on terrestrial ecosystems. Therefore, we examine the sensitivity and response of terrestrial ecosystems to rising moisture stress in India during recent decades (2000 to 2019). The Random Forest approach reveals that soil moisture (SM) is the major driver (31%) of...

The annual formation of an ozone hole in the austral spring has regional and global climate implications. The Antarctic ozone hole has already changed the precipitation, temperature and atmospheric circulation patterns, and thus the surface climate of many regions in the Southern Hemisphere (SH). Therefore, the study of ozone loss variability is im...

The Third Pole (TP) is a high mountain region in the world, and is well-known for its pristine environment, but recent development activities in the region have degraded its air quality. Here, we investigate the spatial and temporal changes of the air pollutants ammonia (NH₃), sulphur dioxide (SO₂) and carbon monoxide (CO) in TP, and reveal their s...

There is a significant increase in ozone at the surface and troposphere due to growing population, industrialization and urbanization. The initiation of National Clean Air Programme (NCAP) in 2019 marked a turning point in addressing air pollution in Indian cities. The Central Pollution Control Board (CPCB) ground-based measurements show a reductio...

CONTEXT About 60% of the world population relies primarily on rice as their staple food, and India ranks second in terms of global rice production. Studies have shown the adverse impact of surface ozone pollution on agriculture, particularly the yield loss (YL) of major staple crops. OBJECTIVE (i) To assess the bias associated with ozone data u...

Precipitable water vapour (PWV) is one of the major factors affecting weather and precipitation extremes. High values of PWV suggest more water available for potential rainfall. Therefore, a thorough understanding of PWV distribution in the atmosphere and its temporal variation are necessary to understand its impact on precipitation intensity. Here...

World's largest highland region, including the Hindukush Himalaya and Tian Shan mountains, with a total area of about 7 million km2 has the largest fresh ice mass outside the poles and referred to as the Third Pole (TP), which is also an ecologically fragile zone of twelve countries. Ten major Asian rivers are nourished by the glacier and snowmelt...

There have been substantial changes in the terrestrial ecosystems across the globe due to climate change as well as anthropogenic activities in recent decades (2000-2019). In the global warming context, moisture stress is likely to be more severe with adverse impact on the terrestrial ecosystems. It is necessary to understand the response of terres...

Atmospheric pollution in the Arctic has been an important driver for the ongoing climate change there. Increase in the Arctic aerosols causes the phenomena of Arctic haze and Arctic amplification. Our analysis of aerosol optical depth (AOD), black carbon (BC), and dust using ground-based, satellite, and reanalysis data in the Arctic for the period...

In recent decades, vegetation cover, photosynthetic activity and productivity across the globe show significant changes owing to climate change and frequent extreme events. Since India is in the tropical region of higher carbon uptake potential and is an agrarian economy, it is imperative to examine the changes in biosphere-atmosphere-hydrosphere i...

The Earth's temperature has witnessed a substantial rise since the start of industrialization. In this study, we delve into the patterns of surface temperature within the arid region of northwest (NW) India. The arid regions across India exhibit remarkable diversity encompassing aspects like climate, topography, soil, wildlife, and human endeavors....

The Thar Desert, alternatively known as the Great Indian Desert, is an arid region characterised by undulating sand dunes in the Indian subcontinent. A part of the desert is in the Indian state of Rajasthan, but it extends from the eastern regions of Pakistan to the Punjab and Sindh Provinces. In recent decades, although climate change has been inf...

Stratospheric ozone is an important constituent of the atmosphere. Significant changes in its concentrations have great consequences for the environment in general and for ecosystems, in particular. Here, we analyse ground-based, ozonesonde and satellite ozone measurements, and reanalysis data to examine the ozone depletion in the tropics, and the...

Temperature measurements are essential to monitor the changes in global and regional weather and climate over a period. Continuous measurements of temperature are used for in-depth analysis of rising temperature in a region, increasing heatwaves or changes in the seasonal temperature distribution. The Indian Space Research Organisation (ISRO) has d...

Nowcasting and short‐range predictions of severe weather events require frequent observations of atmospheric thermodynamic state. To meet these requirements, India has launched a series of advanced weather satellites in geostationary platform, with Indian National Satellite System (INSAT)‐3D and INSAT‐3DR as first two satellites placed in this orbi...

There are substantial changes in global green cover owing to anthropogenic activities and climate change. Here, we estimate the long-term changes in India's green cover, and its contribution from croplands and forests using satellite-based Normalised Difference Vegetation Index (NDVI) and Leaf Area Index (LAI) for the period of 2000–2019. The chang...

The Earth’s surface temperatures have increased significantly since the beginning of industrialisation. The high emissions of greenhouse gases have contributed to global warming and climate change, which is expected to continue. Here, we investigate the long-term trends of surface temperature in India using surface, satellite and reanalysis data fo...

Wetlands are of utmost importance due to their provision of several ecosystem services that are essential to humanity. These services include a wide range of advantages, including the supply of freshwater, provision of food and building materials, support for biodiversity, facilitation of flood control, replenishment of groundwater, and mitigation...

The rise in greenhouse gases (GHGs) induced by human activities causes temperatures to rise both at regional and global scales. The most important GHG, water vapour, has a large positive feedback effect on the Earth's climate system and global warming. It increases the magnitude of climate change in response to natural and human-caused climate vari...

The Asian Summer Monsoon Anticyclone (ASMA) has gained significant attention due to its role in atmospheric dynamics, chemistry and radiative variability. The concentration and spatial distribution of chemical compounds in the upper troposphere and lower stratosphere (UTLS) are strongly influenced by the process of stratosphere-troposphere exchange...

We analyse the long-term (1980-2020) changes in aerosols over the Third Pole (TP) and assess the changes in radiative forcing (RF) using satellite, ground-based and reanalysis data. The annual mean aerosol optical depth (AOD) varies from 0.06 to 0.24, with the highest values of around 0.2 in the north and southwest TP, which are dominated by dust f...

Recently, South Eastern Arabian Sea (SEAS) experiences recurrent winter blooms of green Noctiluca scintillans with serious ecological consequences. Here, the analysis of green N. scintillans blooms in SEAS for the past three consecutive years (2018–2021) is presented. The daily monitoring showed intense winter blooms during November with stable sea...

Climate and agriculture experts emphasize the need to develop a carbon sink in the soil to help alleviate the effects of climate change. A 2‐year field experiment in semiarid tropical drylands tested sustainable nutrient management approaches to sequester carbon in the soil. We analyzed nine different treatments, including chemical fertilizers (as...

At higher concentrations, tropospheric ozone can cause respiratory difficulties, premature human mortality and can harm vegetation by reducing photosynthesis and its growth. It is an oxidant and also an important green- house gas with positive feedback to temperature. It is produced as a byproduct of chemical reactions involving nitrogen oxides (NO...

Among the greenhouse gases (GHGs), atmospheric water vapor is the most abundant, has a large influence on the radiation budget of Earth, and plays a decisive role in regional weather processes. We investigate the long-term (1980–2020) changes in global tropospheric water vapor using satellite, radiosonde, and reanalysis data and assess the impact o...

Global oceanic regions are rapidly changing in terms of their temperature, oxygen, heat content, salinity and biogeochemistry. Since the biogeochemistry of the oceans is important and pivotal for global food production, and a major part of the world population relies on marine resources for their daily life and livelihood, it is imperative to monit...

Middle atmospheric carbon monoxide (CO) has been considered as a dynamical tracer to study the transport in the stratosphere and mesosphere because of its long lifetime. However, most trend studies of CO are limited to troposphere and the Upper Troposphere Lower Stratosphere (UTLS). Here, we investigate the seasonal, annual and long-term changes of...

The COVID-19 lockdown (LD) provided a unique opportunity to examine the changes in regional and global air quality. Changes in the atmospheric carbon monoxide (CO) concentrations during LD warrant a thorough analysis as CO is a major air pollutant that affects human health, ecosystem and climate. Our analysis reveals a decrease of 5-10% in the CO c...

Since its discovery in 1985, the formation of ozone holes in the Antarctic and the resulting ultra-violet (UV) radiation reaching the planet's surface has been a source of major concern. The annual formation of ozone hole in the austral springs has regional and global climate implications. Ozone depletion episodes can change precipitation, temperat...

Carbon Monoxide (CO) is not a greenhouse gas (GHG), but has the capacity to change atmospheric chemistry of other GHGs such as methane and ozone, and therefore indirectly affects Earth's radiative forcing of the GHGs and surface temperature. Here, we use the CO mixing ratio at 850 hPa from the Tropospheric Emission Spectrometer (TES) reanalysis and...

Tropospheric ozone (TPO) is a greenhouse gas and a harmful air pollutant. Changes in TPO directly affect public health, ecosystem and climate. TPO is not directly released to the atmosphere, but as a secondary pollutant formed by the chemical reactions of VOC’s, CO and CH4 in the presence of NOx and sunlight. However, there is a dearth of knowledge...

The increasing population and its associated amenities demand innovative devices, infrastructure, methods, plans and policies. Regional climate has a great role in deciding the air quality and energy demand, and therefore, weather and climate have an indisputable role in its consumption and storage. Here, we present the changes in trace gases and a...

In recent decades, vegetation cover and productivity exhibit substantial variability around the globe. Both climate drivers and human induced changes significantly impact vegetation, which is not adequately explored for the Indian region. Here, we use satellite and reanalysis data to unravel the phenomena driving the greening/browning of India. The...

Amount of ozone in the stratosphere is very small as compared to other trace gases in the atmosphere. Yet, significant changes in its concentrations have great consequences in the environment and ecosystems. However, such drastic changes in ozone happens only in the high and middle latitudes, particularly in the polar spring, where chemical ozone l...

Among all greenhouse gases (GHGs), atmospheric water vapour is the most abundant and has huge influence on the Earth's radiation budget, and plays decisive role in regional weather processes. Unlike other GHGs, which are controlled by emissions, atmospheric water vapour is influenced by the surface temperature. Here, we examine the long-term change...

The Third Pole, Hindu Kush Himalaya (HKH) and Tien Shan mountains, has been closely monitored for the past few decades because of its deteriorating environmental condition. Here, we analyse the spatio-temporal changes in tropospheric NO2 over TP using satellite observations from 2005 to 2020. The highest NO¬2 concentrations (i.e. ≥ 1 × 1015 molec....

Anthropogenic emissions have produced significant amount of carbon dioxide (CO2) in the atmosphere since the beginning of the industrial revolution. High levels of atmospheric CO2 increases global temperature as CO2 absorbs outgoing longwave radiation and re-emits. Though a well-mixed greenhouse gas, CO2 concentration is not uniform in the atmosphe...

Accurate estimation of carbon cycle is a challenging task owing to the complexity and heterogeneity of ecosystems. Carbon Use Efficiency (CUE) is a metric to define the ability of vegetation to sequester carbon from the atmosphere. It is key to understand the carbon sink and source pathways of ecosystems. Here, we quantify CUE using remote sensing...

The Hindu Kush Himalaya and Tien Shan Mountain regions together are called the Third Pole (TP) of Earth, which encompasses ecologically fragile regions of 12 Asian countries. It is the highest mountain chain with the largest reserve of fresh ice mass on the planet outside the northern and southern polar regions. The TP region is experiencing high r...

The improvement in air quality during COVID-lockdown has been vastly studied around the globe. The implications of improved air quality during COVID-lockdown on local environment, meteorology and human health has found a lot of attention. However, its secondary impacts are largely unknown. Since, India is bestowed with vast croplands and lush green...

Air pollution is a big threat to public health, adversely affect ecosystems and changes regional and global climate as some of the pollutants are greenhouse gases. The poor air quality highly challenges India's prospects of achieving its development goals in several ways. Therefore, sustainable solutions for this problem are necessary in a global w...

India has a tropical monsoon climate with significant regional variability in rainfall and temperature, where precipitation is closely connected to precipitable water vapour (PWV). Here, the satellite and reanalysis data are considered to study the spatial and temporal changes of PWV over India in 1980–2020. We have also analysed its potential driv...

Arabian Sea (AS) experiences Chlorophyll-a (Chl-a) blooms during winter and early spring (November-March) mainly due to the changes induced by seasonally reversing monsoon winds and associated processes. The seasonal blooms exhibit distinct regional patterns in their onset, duration, intensity and peak period. Recent changes in ocean dynamics and p...

The direct effect of pandemic induced lockdown (LD) on environment is widely explored, but its secondary impacts remain largely unexplored. Therefore, we assess the response of surface greenness and photosynthetic activity to the LD-induced improvement of air quality in India. Our analysis reveals a significant improvement in air quality marked by...

As the hydroxyl radical (OH) is the cleansing agent of the atmosphere, reduction in its concentration is a great concern for air quality and transport of trace gases across the latitudes and altitudes. In addition, OH determines the lifetime of most trace gases and non-CO2 greenhouse gases in the atmosphere. Since many pollutants have adverse healt...

Climate policies are a set of actions taken to address the effects of climate change, including policies to reduce or remove greenhouse gases from the atmosphere and adapt to climate change. Air quality is an emerging concern as evidence points out the adverse health effects and ecosystem damage from toxic pollutants in the atmosphere. India witnes...