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Water vapor (H2O) is the strongest greenhouse gas in our atmosphere. Hence, accurate measurements and a correct representation in global models of H2O in the upper troposphere/lower stratosphere (UTLS) are important for understanding and projecting climate. Here we compare balloon‐borne measurements of UTLS H2O, performed by cryogenic frostpoint hygrometers (CFH) and meteorological radiosondes (Vaisala RS41) during two intensive field campaigns in the Asian summer monsoon anticyclone region, with humidity data from three products of the European Centre for Medium‐range Weather Forecasts (ECMWF): operational analysis and forecast (termed OPERA), ERA‐Interim reanalysis, and the newly released ERA5 reanalysis. Taking CFH as a reference, we show that OPERA and ERA5 provide a more accurate representation of UTLS H2O than ERA‐Interim. In particular, OPERA and ERA5 similarly overestimate H2O mixing ratios by on average 0.7–0.8 ppmv (14–15%) and 0.7–0.9 ppmv (15–17%) at pressures 60–100 hPa, respectively, and both provide a good representation of the observed vertical distribution (including fine structures) and natural variability of UTLS H2O. In contrast, ERA‐Interim underestimates UTLS H2O by 0.6–1.7 ppmv (14–30%), and it fails to capture relevant features of the vertical distribution of UTLS H2O. At pressures (p) lower than 60 hPa, all three ECMWF products are in good agreement with CFH. Humidity measurements by RS41 show an average dry bias of 0.1–0.5 ppmv (3–9%) compared to CFH for 60–100 hPa, and a moist bias increasing with altitude for p< 60 hPa, exceeding 100% for p< 40 hPa. ECMWF operational and ERA5 data show moist bias (14–17%) in UTLS water vapor compared to cryogenic frostpoint hygrometer (CFH)ERA‐Interim data shows dry bias (14–30%) in UTLS water vapor compared to CFHNew ERA5 reanalysis provides an improved representation of UTLS water vapor compared to ERA‐Interim reanalysis

This bottom‐up modeling study, supported by new population census 2011 data, simulates ozone (O3) and fine particulate matter (PM2.5) exposure on local to regional scales. It quantifies, present‐day premature mortalities associated with the exposure to near‐surface PM2.5and O3concentrations in India using a regional chemistry model. We estimate that PM2.5exposure leads to about 570,000 (CI95: 320,000–730,000) premature mortalities in 2011. On a national scale, our estimate of mortality by chronic obstructive pulmonary disease (COPD) due to O3exposure is about 12,000 people. The Indo‐Gangetic region accounts for a large part (~42%) of the estimated mortalities. The associated lost life expectancy is calculated as 3.4 ± 1.1 years for all of India with highest values found for Delhi (6.3 ± 2.2 years). The economic cost of estimated premature mortalities associated with PM2.5and O3exposure is about 640 (350–800) billion USD in 2011, which is a factor of 10 higher than total expenditure on health by public and private expenditure. PM2.5exposure is causing 570,000 premature mortalitiesEconomic cost of estimated premature mortalities is about 640 billion USDPM2.5should be the primary target for reducing pollution impacts on health

Influence of Nd+3 doping on temperature dependence of dielectric behaviour and dielectric dispersion have been studied in lead germanate single crystal. Nd+3 doping shifts the dielectric maxima towards lower temperature side. Sharp maxima change to diffused one at higher concentration. The shift is attributed to change in delicate balance between short range and long range coulombian forces. Frequency dispersion shows exponential decay of dielectric constant and a significant peak at 3kHz and 60kHz in tanδ for all compositions. An additional peak appears at higher concentration. The observed low frequency dielectric relaxation is of Maxwell-Wagner type.

Pure lead germanate (LG), 0.1 wt% Nd+3 doped (LG.1Nd+3) and 0.2wt% Nd+3 doped (LG.2Nd+3) lead germanate single crystals were grown by controlled cooling of melt. Room temperature pyroelectric coefficient p(T) was found to increase with doping. In LG.1Nd+3 doping enhances p(T) and figure of merit and there by increases the applicability of lead germanate as a pyroelectric detector.

Pure lead germanate (LG), 0·1 wt% Nd+3-doped lead germanate (LG.1Nd+3), 0·2wt% Nd+3-doped lead germanate (LG.2Nd+3) were grown by controlled cooling of melt. Variation of d.c. conductivity was studied in the temperature range 293°K–523°K. Conductivity increases with increasing temperature, showing semiconducting behaviour for all the compositions under study. The activation energy in ferroelectric phase is larger than in paraelectric phase for all the compositions. The result suggests polaron hopping to be a significant contributor to conduction mechanism.