Comparison Tests of the Integration Effect of Surface Temperature by LAPS and STMAS

A statistical analysis of the distribution of convective windstorms and their radar characteristics in Hubei Province, China. Part 2

Accurate estimates of terrestrial hydrologic states and fluxes are, in large part, dependent on accurate estimates of the spatiotemporal variability and uncertainty of land surface forcings, including downwelling longwave (LW) and shortwave (SW) fluxes. However, such characterization of land surface forcings does not always receive proper attention. This study attempts to better estimate LW and SW fluxes, including their uncertainties, by merging different sources of information while considering horizontal error correlations via implementation of a 2D conditioning procedure within a Bayesian framework. A total of 25 experiments were performed utilizing four different, readily available downwelling radiation products. The localized region of space used to constrain horizontal error correlations was defined using an influence length, , specified a priori. Quantitative comparisons are made against an independent, ground-based observational network. In general, results suggest moderate improvement in cloudy-sky LW fluxes and modest improvement in clear-sky SW fluxes during certain times of the year when using the 2D framework relative to a more traditional 1D framework, but only up to a certain influence length scale. Beyond this length scale the flux estimates were typically degraded because of the introduction of spurious correlations. The influence length scale that yielded the greatest improvement in LW radiative flux estimation during cloudy-sky conditions, in general, increased with increasing cloud cover. These findings have implications for improving downwelling radiative flux estimation and further enhancing existing Land Data Assimilation System (LDAS) frameworks.

Errors in top-of-atmosphere (TOA) radiative fluxes from the Clouds and the Earth’s Radiant Energy System (CERES) instrument due to uncertainties in radiance-to-flux conversion from CERES Terra angular distribution models (ADMs) are evaluated through a series of consistency tests. These tests show that the overall bias in regional monthly mean shortwave (SW) TOA flux is less than 0.2 W m−2 and the regional RMS error ranges from 0.70 to 1.4 W m−2. In contrast, SW TOA fluxes inferred using theoretical ADMs that assume clouds are plane parallel are overestimated by 3–4 W m−2 and exhibit a strong latitudinal dependence. In the longwave (LW), the bias error ranges from 0.2 to 0.4 W m−2 and regional RMS errors remain smaller than 0.7 W m−2. Global mean albedos derived from ADMs developed during the Earth Radiation Budget Experiment (ERBE) and applied to CERES measurements show a systematic increase with viewing zenith angle of 4%–8%, while albedos from the CERES Terra ADMs show a smaller increase of 1%–2%. The LW fluxes from the ERBE ADMs show a systematic decrease with viewing zenith angle of 2%–2.4%, whereas fluxes from the CERES Terra ADMs remain within 0.7%–0.8% at all angles. Based on several months of multiangle CERES along-track data, the SW TOA flux consistency between nadir- and oblique-viewing zenith angles is generally 5% (<17 W m−2) over land and ocean and 9% (26 W m−2) in polar regions, and LW TOA flux consistency is approximate 3% (7 W m−2) over all surfaces. Based on these results and a theoretically derived conversion between TOA flux consistency and TOA flux error, the best estimate of the error in CERES TOA flux due to the radiance-to-flux conversion is 3% (10 W m−2) in the SW and 1.8% (3–5 W m−2) in the LW. Monthly mean TOA fluxes based on ERBE ADMs are larger than monthly mean TOA fluxes based on CERES Terra ADMs by 1.8 and 1.3 W m−2 in the SW and LW, respectively.

The High-Spectral Infrared Atmospheric Sounder (HIRAS) is a Fourier transform spectrometer onboard the fourth polar-orbiting FengYun 3D satellite (FY-3D). The FY-3D HIRAS provides interferogram measurements of Earth view radiance spectra in three infrared spectral bands at 29 cross-track positions, each with a $2 \times 2$ array of field of views (FOVs). The HIRAS level 1 radiance data cover the spectral bands from 650 to 1135 cm−1 [long-wave (LW) band], 1210 to 1750 cm−1 [mid-wave (MW) band], and 2155 to 2550 cm−1 [short-wave (SW) band] with a spectral resolution of 0.625 cm−1. The radiometric calibration algorithm and the methods of refining the nonlinearity (NL) and the polarization correction coefficients on orbit are summarized in this article. The NL correction coefficients are derived by minimizing the spread of the responsivity functions derived from the measurements of the internal calibration target with varying temperatures. The polarization correction coefficients are derived from the cold space observations and the routine Earth scene measurements. The radiometric accuracy is assessed by comparing the HIRAS measurements to the collocated Cross-track Infrared Sounder (CrIS) observations and radiance simulations. The results show that, compared to CrIS, the radiometric differences are about 0.3 and 0.7 K for the LW and MW bands, respectively, and 0.5 K for the CO absorption and window regions in the SW band. The consistency of the radiometric calibration among the four FOVs is estimated to be within 0.2 K for most of the spectral domain. Some remaining issues for the FY-3D HIRAS are also discussed.

Abstract. Anthropogenic aerosols play a major role in the Earth–atmosphere system by influencing the Earth's radiative budget and precipitation and consequently the climate. The perturbation induced by changes in anthropogenic aerosols on the Earth's energy balance is quantified in terms of the effective radiative forcing (ERF). In this work, the present-day shortwave (SW), longwave (LW), and total (i.e., SW plus LW) ERF of anthropogenic aerosols is quantified using two different sets of experiments with prescribed sea surface temperatures (SSTs) from Earth system models (ESMs) participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6): (a) time-slice pre-industrial perturbation simulations with fixed SSTs (piClim) and (b) transient historical simulations with time-evolving SSTs (histSST) over the historical period (1850–2014). ERF is decomposed into three components for both piClim and histSST experiments: (a) ERFARI, representing aerosol–radiation interactions; (b) ERFACI, accounting for aerosol–cloud interactions (including the semi-direct effect); and (c) ERFALB, which is due to temperature, humidity, and surface albedo changes caused by anthropogenic aerosols. We present spatial patterns at the top-of-atmosphere (TOA) and global weighted field means along with inter-model variability (1 standard deviation) for all SW, LW, and total ERF components (ERFARI, ERFACI, and ERFALB) and for every experiment used in this study. Moreover, the inter-model agreement and the robustness of our results are assessed using a comprehensive method as utilized in the IPCC Sixth Assessment Report. Based on piClim experiments, the total present-day (2014) ERF from anthropogenic aerosol and precursor emissions is estimated to be −1.11 ± 0.26 W m−2, mostly due to the large contribution of ERFACI to the global mean and to the inter-model variability. Based on the histSST experiments for the present-day period (1995–2014), similar results are derived, with a global mean total aerosol ERF of −1.28 ± 0.37 W m−2 and dominating contributions from ERFACI. The spatial patterns for total ERF and its components are similar in both the piClim and histSST experiments. Furthermore, implementing a novel approach to determine geographically the driving factor of ERF, we show that ERFACI dominates over the largest part of the Earth and that ERFALB dominates mainly over the poles, while ERFARI dominates over certain reflective surfaces. Analysis of the inter-model variability in total aerosol ERF shows that SW ERFACI is the main source of uncertainty predominantly over land regions with significant changes in aerosol optical depth (AOD), with eastern Asia contributing mostly to the inter-model spread of both ERFARI and ERFACI. The global spatial patterns of total ERF and its components from individual aerosol species, such as sulfates, organic carbon (OC), and black carbon (BC), are also calculated based on piClim experiments. The total ERF caused by sulfates (piClim-SO2) is estimated at −1.11 ± 0.31 W m−2, and the OC ERF (piClim-OC) is −0.35 ± 0.21 W m−2, while the ERF due to BC (piClim-BC) is 0.19 ± 0.18 W m−2. For sulfates and OC perturbation experiments, ERFACI dominates over the globe, whereas for BC perturbation experiments ERFARI dominates over land in the Northern Hemisphere and especially in the Arctic. Generally, sulfates dominate ERF spatial patterns, exerting a strongly negative ERF especially over industrialized regions of the Northern Hemisphere (NH), such as North America, Europe, and eastern and southern Asia. Our analysis of the temporal evolution of ERF over the historical period (1850–2014) reveals that ERFACI clearly dominates over ERFARI and ERFALB for driving the total ERF temporal evolution. Moreover, since the mid-1980s, total ERF has become less negative over eastern North America and western and central Europe, while over eastern and southern Asia there is a steady increase in ERF magnitude towards more negative values until 2014.

This paper is the companion paper of Córdoba-Jabonero et al. (2021). It deals with the estimation of the longwave (LW) and net dust direct radiative effect (DRE) during the dust episode that occurred between 23 and 30 June, 2019, and coincided with a mega-heatwave. The analysis is performed at two European sites where polarized-Micro-Pulse Lidars ran continuously to retrieve the vertical distribution of the dust optical properties: Barcelona, Spain, 23–30 June, and Leipzig, Germany, 29–30 June. The radiative effect is computed with the GAME radiative transfer model separately for the fine- and coarse-mode dust. The instantaneous and daily radiative effect and radiative efficiency (DREff) are provided for the fine-mode, coarse-mode and total dust at the surface, top of the atmosphere (TOA) and in the atmosphere. The fine-mode daily LW DRE is small (< 6 % of the shortwave (SW) component) which makes the coarse-mode LW DRE the main modulator of the total dust net DRE. The coarse-mode LW DRE starts exceeding (in absolute values) the SW component in the middle of the episode which produces positive coarse-mode net DRE at both the surface and TOA. Such an unusual tendency is attributed to increasing coarse-mode size and surface temperature along the episode. This has the effect of reducing the SW cooling in Barcelona up to the point of reaching total dust net DRE positive (+0.9 W m−2) on one occasion at the surface and quasi-neutral (−0.6 W m−2) at TOA. When adding the LW component, the total dust SW radiative efficiency is reduced by a factor 1.6 at both surface (on average over the episode, the total dust net DREff is −54.1 W m−2 τ−1) and TOA (−37.3 W m−2 τ−1). A sensitivity study performed on the surface temperature and the air temperature in the dust layer, both linked to the heatwave and upon which the LW DRE strongly depends, shows that the heatwave contributed to reduce the dust net cooling effect at the surface and that it had nearly no effect at TOA. Its subsequent effect was thus to reduce the heating of the atmosphere produced by the dust particles.

Abstract. This paper is the companion paper of Córdoba-Jabonero et al. (2021). It deals with the estimation of the long-wave (LW) and net dust direct radiative effect (DRE) during the dust episode that occurred between 23 and 30 June 2019 and was paired with a mega-heatwave. The analysis is performed at two European sites where polarized micro-pulse lidars ran continuously to retrieve the vertical distribution of the dust optical properties: Barcelona, Spain, 23–30 June, and Leipzig, Germany, 29–30 June. The radiative effect is computed with the GAME (global atmospheric model) radiative transfer model separately for the fine- and coarse-mode dust. The instantaneous and daily radiative effect and radiative efficiency (DREff) are provided for the fine-mode, coarse-mode and total dust at the surface, top of the atmosphere (TOA) and in the atmosphere. The fine-mode daily LW DRE is low (&lt; 6 % of the short-wave (SW) component), which makes the coarse-mode LW DRE the main modulator of the total net dust DRE. The coarse-mode LW DRE starts exceeding (in absolute values) the SW component in the middle of the episode, which produces positive coarse-mode net DRE at both the surface and TOA. Such an unusual tendency is attributed to increasing coarse-mode size and surface temperature throughout the episode. This has the effect of reducing the SW cooling in Barcelona up to the point of reaching total net positive dust DRE (+0.9 W m−2) on one occasion at the surface and quasi-neutral (−0.6 W m−2) at TOA. When adding the LW component, the total dust SW radiative efficiency is reduced by a factor of 1.6 at both surface (on average over the episode the total dust net DREff is −54.1 W m−2 τ−1) and TOA (−37.3 W m−2 τ−1). A sensitivity study performed on the surface temperature and the air temperature in the dust layer, both linked to the heatwave and upon which the LW DRE strongly depends, shows that the heatwave contributed to reducing the dust net cooling effect at the surface and that it had nearly no effect at TOA. Its subsequent effect was thus to reduce the heating of the atmosphere produced by the dust particles.

Cloud radiative effects on surface downwelling fluxes are investigated using datasets from the Atmospheric Radiation Measurement Program (ARM) sites in the tropical western Pacific Ocean (TWP) region. The Nauru Island (Republic of Nauru) and Darwin, Australia, sites show large variability in sky cover, downwelling radiative fluxes, and surface cloud radiative effect (CRE) that is due to El Niño–Southern Oscillation (ENSO) and the Australian monsoon, respectively, whereas the Manus Island (Papua New Guinea) site shows little intraseasonal or interannual variability. At Nauru, the average shortwave (SW) surface CRE varies from −38.2 W m−2during La Niña conditions to −90.6 W m−2during El Niño conditions. The average longwave (LW) CRE ranges from 9.5 to 15.8 W m−2during La Niña and El Niño conditions, respectively. At Manus, the average SW and LW CREs vary by less than 5 and 2 W m−2, respectively, between the ENSO phases. The variability at Darwin is even larger than at Nauru, with average SW (LW) CRE ranging from −27.0 (8.6) W m−2in the dry season to −95.8 (17.0) W m−2in the wet season. Cloud radar measurements of cloud-base and cloud-top heights are used to define cloud types to examine the effect of cloud type on the surface CRE. Clouds with low bases contribute 71%–75% of the surface SW CRE and 66%–74% of the surface LW CRE at the three TWP sites, clouds with midlevel bases contribute 8%–9% of the SW CRE and 12%–14% of the LW CRE, and clouds with high bases contribute 16%–19% of the SW CRE and 15%–21% of the LW CRE.

The organization of tropical deep convection is supported by radiative feedbacks, in which high clouds and moisture anomalies associated with convection imposes anomalous longwave (LW) radiative heating in the atmosphere, further supporting convection. Despite an abundance of studies with numerical simulations, the interactions between tropical convective organization, radiative feedbacks, and the large-scale atmospheric environment have not been examined comprehensively using observations. This presentation examines such interactions among tropical mesoscale organized convection, radiative feedbacks, and the Madden-Julian oscillation (MJO) using a set of observation-derived data products, including retrievals using spaceborne satellites, ground-based precipitation radar, and reanalyses. &amp;#160;The results of this analysis demonstrate that: (1) Higher sea surface temperature and stronger low-level wind shear strength enhance tropical mesoscale convective activity, increasing cirrus cloud cover and LW heating generated per unit precipitation. (2) The estimation of LW cloud-radiative feedback (LW CRF), defined as the LW cloud-radiative heating produced per unit precipitation, is sensitive to the precipitation data set used. (3) Radiatively driven circulations and the associated moistening effects in the MJO can be derived in a weak-temperature-gradient framework and a linear baroclinic model. LW heating moistens the MJO more efficiently than the total apparent heat source, while shortwave (SW) radiative effects dry the MJO. (4) The LW CRF of the MJO is spatially inhomogeneous, with stronger feedbacks over the tropical Indian ocean and to the northwest of Australia, but weaker feedbacks over the tropical western and central Pacific. The spatial pattern may be determined by the spatial distribution of preferred convective types and precipitation efficiency.

Spartina anglica is an invasive alien plant species whose spread threatens the biodiversity of Irish estuarine mudflats, sandflats and saltmarshes. Models have been developed to predict its distribution to facilitate population control and conservation management, but a more precise definition of the wave-related model parameters is required. This study investigates the distribution of established Spartina anglica in Strangford Lough, Northern Ireland, in relation to wave-related hydrodynamic parameters, generated using a numerical computer model for wave generation and propagation in shallow water.The distribution of S. anglica was statistically associated with shorter waves. Longer waves are indicative of deeper water, affect a larger and deeper volume of water and travel at faster speeds than shorter waves. They are, therefore, more likely to disrupt Lough sediment surfaces and uproot S. anglica seedlings, thus limiting establishment. Other simulated wave-related hydrodynamic parameters showed little variation between sites with and without S. anglica.Although input wave parameters were taken for storm conditions, the simulated wave parameters generated by the study did not pass recognised thresholds for initiating sediment transport. To further investigate the linkages between wave-related hydrodynamic parameters and S. anglica establishment, therefore, it may be necessary to re-assimilate the wave model using higher input waves (i.e. exceptional storm waves). This study forms a preliminary basis for understanding interactions between wave-related hydrodynamics and S. anglica establishment and for developing a predictive model of S. anglica distribution patterns.

Introduction: Tryoshnadi Guggulu Vati, a polyherbal formulation is recommended for the management of diseases due to Medodushti (abnormal fat metabolism) like obesity, diabetes mellitus, dyslipidemia, coronary artery diseases, etc. Though Tryoshnadi Guggulu Vati is widely used for the treatment of diseases due to abnormal metabolism, but till date, its pharmacognostical and pharmaceutical study has not been carried out. Aim: Authentication of raw drug of Tryoshnadi Guggulu Vati and phytochemical evaluation of finished product. Materials and Methods: The present study deals with the pharmacognostical identification of the ingredients of Tryoshnadi Guggulu Vati and its physicochemical analysis. Results: Powder microscopy revealed the presence of annularvessels of Musta, starch grains of Vacha, stone cells of Pippali, stone cells of Chitraka, oleoresins of Shunthi, starch grains of Musta,etc., Physicochemical parameters such as total ash value (15.91%), water soluble extract (13.5%), methanol soluble extract (17.2%)were assessed in preliminary physicochemical scanning. High‐performance thin layer chromatography (HPTLC) revealed maximum 10 spots in short wave ultraviolet (UV) 254 nm. And four spots were obtained in long wave UV 366 nm. Conclusion: Pharmacognostical study revealed genuinity of raw drugs. Physicochemical and HPTLC studies inferred that the formulation meets the minimum quality standards as reported in the American Petroleum Institute at a preliminary level. The inference from this study may be used as reference standard in the further quality control researches. Key words: High‐performance thin layer chromatography, pharmacognosy, physicochemical analysis, Tryoshnadi GugguluVati

Magnetic reconnection in Z-pinch plasma have been measured using ultra high speed laser schlieren technology. Through measurement of plasma distribution of two wires on the XP-1, it is demonstrated that study of magnetic reconnection in Z-pinch plasma is feasible through ultra high speed optic electronic framing camera and schlieren technology. The results of two tungsten wire experiment indicate that the wires start expanding 10 ns after current loading at approximately 8 km/s, and in inner and outer sides of the wires, there are highly possible electrothermal instability vertical to magnetic field. The results of two tungsten wire experiment indicate that the early instability wavelength is 0.4 mm and becomes 1.5 mm at later stage, there is still plenty of plasma in the initial position after current peak. These phenomena reveal a principal characteristic of instability: as it develops, the long wave mode will be dominant and the short wave mode will be restrained.

Horizontal profiles of longwave and shortwave radiation, temperature, humidity, and photographs at Barrow, Alaska, observations on day 3, 2011-06-07

Influence of Hamoun Lakes' dry conditions on dust emission and radiative forcing over Sistan plain, Iran

The clear‐sky aerosol top of atmosphere shortwave (SW) and longwave (LW) radiative effects over the Saharan desert (15–30°N, 10°W–30°E) are investigated based entirely on the satellite observations of aerosol optical thickness (AOT), surface albedo, surface temperature, surface emissivity, atmospheric water vapor content, and SW/LW fluxes. The Ozone Monitoring Instrument (OMI) on Aura and the Multi‐angle SpectroRadiometer (MISR) on Terra satellite are used to estimate AOT at 558 nm (EAOT) for June to September, 2005–2006 when the predominant aerosol type is dust. We then use these EAOT values in conjunction with broadband measurements from the Clouds and the Earth's Radiant Energy System (CERES) to calculate the top‐of‐atmosphere SW and LW flux radiative effect due to these aerosols. The difference in SW flux between desert surface and dust aerosols is found to be negligible due to the high surface reflectance over the Sahara desert. The instantaneous area‐averaged LW radiative effect is calculated as +11.4 Wm−2 with radiative efficiencies ranging from +11 to +26 Wm−2/AOT. The results indicate that net radiative effect of dust over the Sahara desert is dominated by the longwave effect in contrast to oceans where the shortwave effect dominates.