Three-year black carbon aerosol synthesis over a pristine location surrounded by hillocks in Haryana state, India.

The three-year Black Carbon (BC) aerosol measurements made during 2020, 2021, and 2022 over a rural location, namely, Panchgaon, surrounded by Aravali hillocks (elevation of about 400-600 m) have been analyzed with an aim to determine their optical and radiative characteristics, seasonal and long-term variations in mass concentration. The affinity between these parameters and associated pollutants and planetary boundary layer height (PBLH), affected by the orography, to delineate their role in mass concentration changes with time have been investigated. The coincident OPAC (Optical Properties of Aerosols and Clouds) Model-derived aerosol optical depth (AOD), and single scattering albedo (SSA) have been compared with the observed BC mass concentration, and also with synchronous satellite measurements. The year-to-year variability analysis of the data reveals that the rate of increase of BC concentration is high. The variability was low due to the reasons explained. It implies that the year-to-year variability in BC concentration at the study site depends on the source strength modulated by the valley-driven meteorology. Added, the percentage departures of BC concentration show positive values (higher concentration) during morning and evening hours, which could be due to more anthropogenic activities while it shows negative values during afternoon hours and lower boundary layer heights. The force exerted by the radiation due to BC aerosols at the bottom of the atmosphere (BOA), and in the atmosphere (ATM) are almost equal in magnitude and negative, while that at the top-of-the-atmosphere (TOA) is smaller and positive, indicating that BC aerosols in the study region cools the atmosphere at the BOA and warms the ATM and TOA, which indirectly reveals the dominant role of long-range transport phenomenon at higher levels as compared to the surface level.

Double blanket effect caused by two layers of black carbon aerosols escalates warming in the Brahmaputra River Valley.

First ever 3-day aircraft observations of vertical profiles of Black Carbon (BC) were obtained during the Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX) conducted on 30(th) August, 4(th) and 6(th) September 2009 over Guwahati (26° 11'N, 91° 44'E), the largest metropolitan city in the Brahmaputra River Valley (BRV) region. The results revealed that apart from the surface/near surface loading of BC due to anthropogenic processes causing a heating of 2 K/day, the large-scale Walker and Hadley atmospheric circulations associated with the Indian summer monsoon help in the formation of a second layer of black carbon in the upper atmosphere, which generates an upper atmospheric heating of ~2 K/day. Lofting of BC aerosols by these large-scale circulating atmospheric cells to the upper atmosphere (4-6 Km) could also be the reason for extreme climate change scenarios that are being witnessed in the BRV region.

Vertical profiles of black carbon aerosols over the urban locations in South India.

Vertical profiles of black carbon (BC) aerosol were determined from aircraft measurements under the Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX) program conducted by the Indian Institute of Tropical Meteorology, India during 2009 over Bangalore and Hyderabad in south India. BC mass loadings decreased approximately monotonically from 10(3) to 10(4) ng/m(3) at the surface to ~10(2) ng/m(3) at an altitude of about 7 km; although layers at intermediate levels containing anomalously high BC loadings were frequently encountered that were attributed mainly to the convective transport from surface sources accompanied by changes in the local boundary layer and atmospheric stability. In addition, as evidenced from air mass back trajectories; long range transport from distant sources contributed to some anomalous spikes in BC concentration. The presence of BC in cloud forming regions of the free troposphere could have important implications for cloud microphysics and subsequent rainfall mechanism over this region. Apart from this, the effects on human health are equally important.

Acute regional ileitis with concomitant pulmonary tuberculosis.

A case of acute segmental inflammation of the terminal ileum in a female patient, who presented with signs and symptoms of acute appendicitis is reported. She had an associated bilateral pulmonary tuberculosis. The role of Mycobacterium tuberculosis in the etiology of the segmental ileal disease, and the relationship of the acute disease of the ileum to Crohn's disease is discussed. Henoch's purpura whose intestinal manifestations may mimic acute regional ileitis is discussed in the differential diagnosis.