Tropical forests, which play critical roles in global biogeochemical cycles, radiation budgets and biodiversity, have undergone rapid changes in land cover in the last few decades. This study examines the complex process of land cover change in the biodiversity hotspot of Western Ghats, India, specifically investigating the effects of conservation measures within the Indira Gandhi Wildlife Sanctuary. Current vegetation patterns were mapped using an IRS P6 LISS III image and this was used together with Landsat MSS data from 1973 to map land cover transitions. Two major and divergent trends were observed. A dominant degradational trend can be attributed to agricultural expansion and infrastructure development while a successional trend, resulting from protection of the area, showed the resilience of the system after prolonged disturbances. The sanctuary appears susceptible to continuing disturbances under the current management regime but at lower rates than in surrounding unprotected areas. The study demonstrates that remotely sensed land cover assessments can have important contributions to monitoring land management strategies, understanding processes underpinning land use changes and helping to inform future conservation strategies.

Abstract. The transport of aerosols and pollutants from continental India to the adjoining oceanic areas is a major topic of concern and several experimental campaigns have been conducted over the region focusing on aerosol characteristics and their climate implications. The present study analyzes the spectral aerosol optical depth (AOD) variations over Bay of Bengal (BoB) during Winter-Integrated Campaign for Aerosols, gases and Radiation Budget (W-ICARB) from 27 December 2008 to 30 January 2009 and investigates the influence of the adjoining landmass to the marine aerosol field. High AOD 500 values (>0.7) occurred over northern BoB due to outflow of aerosols and pollutants from the densely populated Indo-Gangetic Plains (IGP); low AOD 500 (0.1-0.2) was observed in central and southern BoB, far away from the mainland. The Angstrom exponent "α" was observed to be high (>1.2) near coastal waters, indicating relative abundance of accumulation-mode continental aerosols. On the other hand, over southern BoB its values dropped below ∼0.7. National Center for Environmental Prediction (NCEP) reanalysis data on winds at 850 and 700 hPa, along with airmass trajectories calculated using Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, suggested transport of continental aerosols from central and northern India over the BoB. On the other hand, when the ship was crossing the eastern BoB, the aerosol loading was strongly affected by air-masses originating from Southeast Asia, causing an increase in AOD and α. Biomass-burning episodes over the region played an important role in the observed aerosol properties. Terra/Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) AOD 550 and cruise measured AOD 550 showed good agreement (R 2 = 0.86 and 0.77, Correspondence to: S. K. Kharol (shaileshan2000@yahoo.co.in) respectively) over BoB, exhibiting similar AOD and α spatiotemporal variation.

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In the present study we have attempted to characterize aerosols using their optical properties over a tropical urban location of Hyderabad, India. We have analyzed three years of in-situ data on aerosol absorption from Aethalometer and scattering from Nephelometer measurements. Satellite based absorption measurements from ozone monitoring instrument, absorbing aerosol index are also analyzed to investigate the role of long range transport of dust. Further, the CloudAerosol Lidar Pathfinder Satellite Observations (CALIPSO) data is used to study the vertical extent of aerosol particles as well as their sphericity using its particulate depolarization ratio. The study revealed that irrespective of seasonal variation, local anthropogenic fossil fuel aerosols form the predominant aerosol type over this site. Biomass/dust aerosols in their pure form are not present during the study period; however the spread of frequency distribution of scattering Angstrom exponent and absorption Angstrom exponent suggested their possible existence in mixed condition with local anthropogenic aerosols. The analysis of columnar aerosol absorption data during pre-monsoon period showed the dominance of UV absorbing dust aerosols in the study region. CALIPSO data analysis over study area showed that majority aerosols are confined within 2 km from the surface during winter while in pre-monsoon particles are distributed throughout the profile (~6 km) with extinction coefficient varying between 0.1-0.2 km -1 . As the season shift from winter to pre-monsoon a change in sphericity of particle is observed. Cluster mean trajectory analysis revealed that during premonsoon majority of air mass movements (~68%) are from western side passing through dust source region like Persian Gulf and Thar Desert before entering into Indian region. During post-monsoon (~70%) and winter (~65%), majority of the air masses are coming from north-west and north-east side of the study area where biomass burning is quite frequent during this period.