The INCOMPASS field campaign combines airborne and ground measurements of the 2016 Indian monsoon, towards the ultimate goal of better predicting monsoon rainfall. The monsoon supplies the majority of water in South Asia, but forecasting from days to the season ahead is limited by large, rapidly developing errors in model parametrizations. The lack of detailed observations prevents thorough understanding of the monsoon circulation and its interaction with the land surface: a process governed by boundary‐layer and convective‐cloud dynamics. INCOMPASS used the UK Facility for Airborne Atmospheric Measurements (FAAM) BAe‐146 aircraft for the first project of this scale in India, to accrue almost 100 h of observations in June and July 2016. Flights from Lucknow in the northern plains sampled the dramatic contrast in surface and boundary‐layer structures between dry desert air in the west and the humid environment over the northern Bay of Bengal. These flights were repeated in pre‐monsoon and monsoon conditions. Flights from a second base at Bengaluru in southern India measured atmospheric contrasts from the Arabian Sea, over the Western Ghats mountains, to the rain shadow of southeast India and the south Bay of Bengal. Flight planning was aided by forecasts from bespoke 4 km convection‐permitting limited‐area models at the Met Office and India's NCMRWF. On the ground, INCOMPASS installed eddy‐covariance flux towers on a range of surface types, to provide detailed measurements of surface fluxes and their modulation by diurnal and seasonal cycles. These data will be used to better quantify the impacts of the atmosphere on the land surface, and vice versa. INCOMPASS also installed ground instrumentation supersites at Kanpur and Bhubaneswar. Here we motivate and describe the INCOMPASS field campaign. We use examples from two flights to illustrate contrasts in atmospheric structure, in particular the retreating mid‐level dry intrusion during the monsoon onset.

Abstract:We study general two-body decays of primitive and non-primitive 1 4 -BPS dyons in four-dimensional type IIB string compactifications. We find a "master equation" for marginal stability that generalises the curve found by Sen for 1 2 -BPS decay, and analyse this equation in a variety of cases including decays to 1 4 -BPS products. For 1 2 -BPS decays, an interesting and useful relation is exhibited between walls of marginal stability and the mathematics of Farey sequences and Ford circles. We exhibit an example in which two curves of marginal stability intersect in the interior of moduli space.

EddyPro checks for signal quality and gas analyzer signal strength (which depends on the cleanliness of sensor optical windows and/or presence or absence of rain drops/fog in the measuring volume). A missing samples allowance of 10% was set for the raw data in the flux averaging intervals and linear interpolation of the data is done by Eddy pro within this limit. The effect of wind blowing normal to the sonic path on the speed of sound (sonic temperature) is corrected for in the CSAT3 firmware(CSAT3 3-D Sonic Anemometer Instruction Manual). Other corrections are as follows.

Plant growth processes and productivity of agroecosystems depend highly on evapotranspiration from the land (soil-crop cover complex) surface. A study was carried out using MODIS TERRA optical and thermal band data and ground observations to estimate evaporative fraction and daily actual evapotranspiration (AET) over agroecosystems in India. Five study regions, each covering a 10 km610 km area falling in agricultural land use, were selected for ground observations at a time closest to TERRA overpasses. The data on radiation and crop parameters in paddy (irrigated and rainfed), cotton (rainfed), groundnut (residual moisture) crops were recorded at 14-day intervals between August 2003 to January 2004 from 2 km62 km homogeneous crop patches within each study region. Eight MODIS scenes in seven optical (1, 2, 3, 4, 5, 6, 7) and two thermal bands (31, 32) level 1B data acquired from the National Remote Sensing Agency, Hyderabad, India and resampled at 1 km, were used to generate surface albedo (a), land surface temperature (T s, MODIS ) and emissivity (e s ). Evaporative fraction and daily AET were generated using a single source energy balance approach with (i) ground based observations only ('stand alone' approach), and (ii) 'fusion' of MODIS derived land surface variables on cloud free dates and coincident ground observations. Land cover classes were assigned using a hierarchical decision rule applied to multi-date Normalized Difference Vegetation Index (NDVI). The exponential model could be fitted between 1-EF ins, ground (ground based evaporative fraction) and difference between T s, MODIS and air temperature (T a ) with R 2 50.77. Linear fit (R 2 50.74) could be obtained between 1-EF ins, ground and temperature vegetation dryness index (TVDI), derived from T s, MODIS -NDVI triangle. Energy balance daily AET from the 'fusion' approach was found to deviate from water balance AET by between 4.3% to 24.5% across five study sites with a mean deviation of 11.6%. The root mean square error (RMSE) from the energy balance AET was found to be 8% of the mean water balance AET. The satellite based energy balance approach can be used to generate spatial AET, but needs more refinements before operational use in the light of progress in algorithms and their validation with huge datasets.

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