Abstract. Reliable data on circumsolar radiation, which is caused by scattering of sunlight by cloud or aerosol parti- cles, is becoming more and more important for the resource assessment and design of concentrating solar technologies (CSTs). However, measuring circumsolar radiation is de- manding and only very limited data sets are available. As a step to bridge this gap, a method was developed which al- lows for determination of circumsolar radiation from cirrus cloud properties retrieved by the geostationary satellites of the Meteosat Second Generation (MSG) family. The method takes output from the COCS algorithm to generate a cirrus mask from MSG data and then uses the retrieval algorithm APICS to obtain the optical thickness and the effective ra- dius of the detected cirrus, which in turn are used to deter- mine the circumsolar radiation from a pre-calculated look-up table. The look-up table was generated from extensive cal- culations using a specifically adjusted version of the Monte Carlo radiative transfer model MYSTIC and by developing a fast yet precise parameterization. APICS was also improved such that it determines the surface albedo, which is needed for the cloud property retrieval, in a self-consistent way in- stead of using external data. Furthermore, it was extended to consider new ice particle shapes to allow for an uncertainty analysis concerning this parameter.
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The LSA SAF has been especially designed to serve the needs of the NRT meteorological community, particularly for Numerical Weather Prediction (NWP). Satellite observations of the surface of the Earth are today routinely assimilated in weather prediction models with significant impacts on their representation of land surface processes . The LSA SAF also addresses other communities including users interested in climatological applications who require long and homogeneous time series. The delivered satellite products exploit data acquired from the instruments on board the Meteosat Second Generation (MSG) platform and the Meteorological-Operational (Metop) satellites. The product portfolio of the LSA SAF comprises variables such as temperature, short-wave and long-wave downwelling radiation and turbulent fluxes (including evapotranspiration), leaf area index and vegetation cover fraction, and surface albedo. In addition to the NRT production of these biophysical variables, a first long term reprocessed time series (called Climate Data Record, CDR) of several of these biophysical variables (including land surface albedo) was made available to the community in 2018.
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Abstract. Novel methods of cloud detection are applied to airborne remote sensing observations from the unique Fennec aircraft dataset, to evaluate the Met Office-derived products on cloud properties over the Sahara based on the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) on-board the Meteosat Second Generation (MSG) satellite. Two cloud mask configurations are considered, as well as the retrievals of cloud-top height (CTH), and these prod- ucts are compared to airborne cloud remote sensing prod- ucts acquired during the Fennec campaign in June 2011 and June 2012. Most detected clouds (67 % of the total) have a horizontal extent that is smaller than a SEVIRI pixel (3 km × 3 km). We show that, when partially cloud- contaminated pixels are included, a match between the SE- VIRI and aircraft datasets is found in 80 ± 8 % of the pixels. Moreover, under clear skies the datasets are shown to agree for more than 90 % of the pixels. The mean cloud field, de- rived from the satellite cloud mask acquired during the Fen- nec flights, shows that areas of high surface albedo and orog- raphy are preferred sites for Saharan cloud cover, consistent with published theories. Cloud-top height retrievals however show large discrepancies over the region, which are ascribed to limiting factors such as the cloud horizontal extent, the de- rived effective cloud amount, and the absorption by mineral dust. The results of the CTH analysis presented here may also have further-reaching implications for the techniques
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The diurnal or daytime cycle of satellite-derived LWP has been well documented in several studies (Wood et al., 2002; O’Dell et al., 2008; Painemal et al., 2012), mainly for specific regions such as the west coast of South America (Painemal et al., 2012). The good temporal resolution and high spa- tial coverage of measurements from geostationary satellites qualifies the derived cloud properties even more to be anal- ysed concerning their diurnal variability. Early LWP studies with GOES 9 measurements were carried out by Greenwald and Christopher (1999); an analysis of LWP diurnal cy- cle in marine-boundary-layer clouds with respect to aerosol load was undertaken by Chellappan (2011). Comparisons to regional climate model simulations of SEVIRI-derived cloud amount and LWP can be found in Roebeling and Van Meijgaard (2009) as well as Pfeifroth et al. (2012). Roebeling and Van Meijgaard (2009) proved the suitability of SEVIRI- derived cloud amount and LWP for climate model evalua- tion. In our study, we go beyond the simplified type of cloud approach and analyse and discuss the relationship between cloud type and liquid water path as they are categorised by CM SAF (EUMETSAT’s Satellite Application Facility on Climate Monitoring). Both variables are derived from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard the Meteosat Second Generation 2 (MSG 2) satel- lite. Characteristic features of LWP concerning its distribu- tion and diurnal cycle for the individual cloud types are ex- plored. The results of the one year time-frame are put into context with the University of Wisconsin (UWisc) cloud liq- uid water path climatology derived from 18 years of pas- sive microwave observations (see O’Dell et al., 2008). The general features of LWP, for example, frequency distribu- tion, average value and diurnal cycle are specified to serve as characteristic measures in atmospheric numerical mod- elling. More specifically, they can be used to conduct pro- cess studies, assist in the evaluation of microphysical mea- surement experiments such as the airborne probing of clouds and serve as input for cloud generators and radiative trans- fer studies on a wide range of spatial scales. The temporal
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a pattern recognition algorithm trained and tested on differ- ent sets of RR measurements obtained from NOAA opera- tional radars. They classify rain into three classes (non-rainy, light rainy, heavy rainy classes). Adler et al. (1993) were the first to successfully combine the advantages of both types of instrument by using matched MW and IR data. Vicente et al. (1998) introduced the auto-estimator in order to esti- mate rainfall from GOES measurements focusing on heavy precipitation. The auto-estimator differs from the previous IR methods for rainfall estimation because it considers other factors in addition to the IR window cloud top temperature. In particular, information about environmental moisture is used to obtain a more correct estimation of rainfall as well as for the screening of the non-rainy pixels. Ba and Gru- ber (2001) used the GOES visible (0.65 µm), near-infrared (3.9 µm), water vapour (6.7 µm) and window channels (10.7 and 12.0 µm) to estimate rainfall rate, distinguishing raining from non-raining clouds by taking into account the cloud top temperature, the effective radius of cloud particles and the temperature gradient. Moreover, in an attempt to give more reliable values of rain rates, Ba and Gruber (2001) used the moisture factor correction developed by Scofield (1987) and modified by Vicente et al. (1998). Other authors used arti- ficial neural networks to derive precipitation estimates us- ing satellite IR images (Hsu et al., 1997; Behrangi et al., 2009; Capacci and Porcù, 2009). Many authors developed techniques to determine RR from Meteosat data, both phys- ical and statistical. Physical techniques consist of brightness temperature difference threshold tests or consider effective radius as well as cloud top height/temperature in order to de- termine rainfall rate and/or probability by the use of look- up tables. The look-up tables are usually built by consider- ing rainfall measurements obtained through rain-gauge in- struments or radar
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This HRV-based cloud mask is part of our wider effort to extend the cloud physical properties retrieval (Roebeling et al., 2006; Roebeling et al., 2008) to the high spatial res- olution of the HRV channel, including an estimate of cloud optical thickness (Carbajal Henken et al., 2011) and other cloud properties. It offers also the possibility of applying the cloud mask as a tool to study the geometric size of convective clouds including their temporal evolution in the future. Simi- lar approaches will be essential to utilize the data from future satellite missions optimally, such as Meteosat Third Gener- ation, whose imager has different spatial resolutions for the solar and infrared channels. For a disk-wide application of the HRV cloud mask, more regions with a higher amount of cirrus clouds or high aerosol loads should be considered.
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Abstract. Solar radiation plays a key role in the Earth’s energy balance and is used as an essential input data in radiation-based evapotranspiration (ET) models. Accurate gridded solar radiation data at high spatial and temporal res- olution are needed to retrieve ET over large domains. In this work we present an evaluation at hourly, daily and monthly time steps and regional scale (Catalonia, NE Iberian Penin- sula) of a satellite-based solar radiation product developed by the Land Surface Analysis Satellite Application Facility (LSA SAF) using data from the Meteosat Second Genera- tion (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI). Product performance and accuracy were evalu- ated for datasets segmented into two terrain classes (flat and hilly areas) and two atmospheric conditions (clear and cloudy sky), as well as for the full dataset as a whole. Eval- uation against measurements made with ground-based pyra- nometers yielded good results in flat areas with an averaged model RMSE of 65 W m −2 (19 %), 34 W m −2 (9.7 %) and 21 W m −2 (5.6 %), for hourly, daily and monthly-averaged solar radiation and including clear and cloudy sky conditions and snow or ice cover. Hilly areas yielded intermediate re- sults with an averaged model RMSE (root mean square er- ror) of 89 W m −2 (27 %), 48 W m −2 (14.5 %) and 32 W m −2 (9.3 %), for hourly, daily and monthly time steps, suggesting the need of further improvements (e.g., terrain corrections) required for retrieving localized variability in solar radiation in these areas. According to the literature, the LSA SAF solar radiation product appears to have sufficient accuracy to serve as a useful and operative input to evaporative flux retrieval models.
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Since the launch of EO satellites, such as Meteosat Second Generation (MSG), and Sentinel satellite series, real-time image processing techniques have been developed (Suárez and Nesmachnow, 2012). The main advantage of these tech- niques is the possibility to monitor numerous meteorologi- cal variables in almost real time (Derrien et al., 2005; Me- teoFrance, 2013). A comprehensive intercomparison of radi- ation products, codes, algorithms, models and independent databases has been performed by many researchers (Ore- opoulos and Mlawer, 2010; Oreopoulos et al., 2012; Elling- son et al., 1991; Ineichen, 2006; Beyer et al., 2009; Ca- halan, et al., 2005). Solid steps in estimating the surface GHI were taken by Deneke and Feijt (2008), Schulz et al. (2009), Mueller et al. (2009), Huang et al. (2011) and Qu et al. (2017), who developed GHI retrieval methodologies based on the use of discrete pre-calculated look-up tables (LUTs), while Dorvlo et al. (2002), Zarzalejo et al. (2005), Lopez et al. (2001) and Takenaka et al. (2011) developed solutions based on neural network (NN) models. The vali- dation of most of the above mentioned methodologies was performed against radiative transfer model (RTM) simula-
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aquaculture management, near-real-time alerting to harmful algae blooms, environmental monitoring and forecasting, and assessment of sediment transport in coastal waters. Ocean colour data from polar-orbiting satellite platforms, however, suffer from fractional coverage, primarily due to clouds, and inadequate resolution of quickly varying processes. Ocean colour remote sensing from geostationary platforms can provide significant improvements in coverage and sampling frequency and support new applications and services. EUMETSAT’s SEVIRI instrument on the geosta- tionary Meteosat Second Generation platforms (MSG) is not designed to meet ocean colour mission requirements, however, it has been demonstrated to provide valuable contribution, particularly in combination with dedicated ocean colour polar observations. This paper describes the ongoing effort to develop operational ocean colour water turbidity and related products and user services from
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Abstract: This article given a second generation current controlled current conveyor positive (CCCII+), second generation current controlled current conveyor negative (CCCII-), Quadrature oscillator with high-Q frequency choosing network and implementing completely different phase oscillators by employing (CCCII+) positive and (CCCII-) negative, and high band pass filter network, the approach is predicted on the CMOS technology . The root of this concept is, considering a customary voltage mode oscillator which consists of band pass filter with prime quality issue (high-Q) and voltage mode amplifier is transfigure into current mode oscillator by replacing tans-conductance amplifier. Because the loop of the oscillator is has lavish selectivity, the oscillator process less distortion. In addition 3dB bandwidth, oscillating condition, oscillation frequency of the oscillator could linearly, independently and electronically be tuned by adjusting the bias current of the (CCCII±), lastly different simulations have been carried out to verify the linearity between output and input ports, range of frequency operations. These results can justify that the designed circuits are workable.
The NAO influenced the timing, or phenology, of the butterfly flight season for all six species studied in detail. The peak flight weeks for An. cardamines, M. galathea, A. hyperantus and P. tithonus (Fig. 3), and the peak flight weeks for both the first and second generations of L. megera and P. icarus (Fig. 4) were earlier in positive NAO index years. These results were similar to those found for the green spruce aphid, E. abietinum, which flew earlier in years with a more positive winter NAO index (Westgarth-Smith et al., 2007). The fact that correlation coefficients between peak flight week and the winter NAO index were higher than those between annual collated indices and the winter NAO index indicated that the NAO had a stronger relationship with butterfly phenology than with abundance. The NAO index is very difficult to predict and hence although the it can be used to predict flight timing, it would be difficult to do so in December, but feasible to do so by the end of March because by then the winter NAO index is known.
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The first indicator about participation in activities refers to the last 12 months before the respondent fills in the questionnaire. The answer possibilities are yes and no. The second indicator, the frequency of contact is divided into seven categories. These are; almost every day, 1-2 times a week, few times per month, once a month, a number of times per year, once a year and never. Also these categories are re-coded for this research where almost every day and 1-2 times a week are called ‘weekly’, few times per month and once a month is called ‘monthly’, a number of times per year and once a year are called ‘annually’ and the last category ‘never’. Then the last indicator of this sub-question about satisfaction has a scale from 1 to 10 to answer the question. For this research, the respondents giving a 6 or higher are considered as ‘satisfied’ with their social contacts, while the group giving a 5 or lower, are considered as not satisfied. This is divided this way because within the Netherlands, the grading system says that a ‘1’ is the lowest, and a ‘10’ is the highest number you can give. Whereas giving a ‘5’ is lower than the satisfactory level (5,5).
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The need to produce cheap renewable fuels to replace fos- sil fuels is reflected in the political agendas of many coun- tries, aimed at the development of a reliable energy source to ensure fuel security, promote rural development and to address climate change by reducing greenhouse gases emission [1-5]. Among the alternative biofuels, ethanol from sugarcane can provide a substantial contribution in terms of the amount produced and the environmental im- pact, especially if the lignocellulosic fraction of the sugar- cane is also used for fuel production [6-9]. Indeed, high volumes of second generation (2G) ethanol can be pro- duced from sugarcane bagasse and leaves, which are the residues of the current sugarcane-to-ethanol industry. 2G technology is not as mature as first generation (1G) etha- nol production, and is thus less economically feasible. However, some companies have set out to demonstrate its feasibility through the construction of commercial-scale plants [10-12]. The availability of sugarcane for ethanol production is affected by volatility on the world market due, in part, to the demand for this raw material to make sugar for the food industry [13,14]. Bagasse and leaves are also combusted to generate bioelectricity, espe- cially in areas where there are no other means of generat- ing electricity, or only seasonably available sources. For instance, in Brazil, hydropower is the main source of electricity, while sugarcane residues can provide a suit- able complement during the dry season [15-17]. More- over, biorefineries producing alternative and/or more profitable commodities than ethanol from sugar- and lignin-containing materials may reduce the long-term profitability of ethanol plants due to raw material com- petition [18,19].
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With regard to their experiences in the city, “ second-generation groups are more ‘ native ’ to their city of residence than their peers of non-migrant parentage ” (Crul et al., 2012, p. 312). They are indeed one of the most “established” populations in cities, due to their length of time living in the cities (Crul, 2016). This might be one reason why for the second generation, a strong sense of belonging to the city is less complicated than a strong sense of belonging to the nation itself. For the native comparison group, this difference is less pronounced, or even reversed. Even more important for identification than the city is the neighborhood. Many of the second generation respondents in the TIES study had lived in the same neighborhood for many years and felt attached to it, which they also expressed by a high level of involvement in local affairs, an illustration of their place-making practices. In other words, the second-generation is more likely to have local, place-based connections than national, state-level ones. In general, the TIES study thus shows the importance of the local integration context, which can reinforce or weaken national discourses around who belongs to the nation. Existing research also demon- strates the importance of the local context for identity formation (Vathi, 2013).
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radiates ~ 10 -3 photon/second under the same excitation intensity (~ 10 kW/cm 2 average intensity), which is extremely weak for detection. The excitation may be increased by an order of magnitude since it is only 1% of the cell damage threshold. This will lead to SHG signal of ~ 0.1 photon/second, which is still very weak. The low SHG conversion efficiency compared to fluorescence is the result of nonresonant SHG process. The nonresonant nature provides us a flexible choice in the excitation wavelength. In our laboratory, it has been demonstrated that the SHG efficiency can be enhanced 500 times by creating a plasmonic resonant nanoshell around the nanoparticle, and an enhancement of 3500 is theoretically possible . Through engineering the plasmonic resonance of the nanoprobes, wavelength multiplexing can be achieved. One can also improve the conversion efficiency by using other materials which have stronger second-order nonlinearity. Recently, SHG from a CdTe/CdS core/shell quantum dot with a diameter of < 15 nm has been observed . For biological applications, the cytocompatibility of these new nonlinear materials should be carefully examined.
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The approach for inter-calibration of polar-orbiting im- agers using the geostationary SEVIRI as a transfer instru- ment has the advantage of daily availability of collocated reflectances. Since both clear and cloudy pixels are used, a large dynamic range of reflectances is obtained and robust statistics can be developed. The method allows verifying cal- ibrations based on polar–polar SNOs, which typically occur at high latitudes only. An obvious limitation of the method is that a geostationary sensor with the appropriate solar chan- nels is required, which reduces the applicability backward in time. With the SEVIRI record already spanning almost ten years and a similar time period to come, and with the up- coming Meteosat Third Generation as well as other new geo- stationary imagers, the applicability of the method is guar- anteed in the far future, for even more channels than used in this study.
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Mutation with M351T was known to be sensitive to all 3 TKIs, but it was detected when our patient had a cytogenetic failure as well as a hematologic failure. This patient never had an optimal response to nilotinib but had always maintained a CHR and later showed molecular failure. A second new mutation E255V was seen which had an intermediate resistance to nilotinib and dasatinib.
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cultural ‘dupes’ whose social practices are fully determined by the social structures in which they operate. Instead they are capable of reflecting upon their use of language and the structures that constrain it. However, this is not to say that human agents are free to change strategic culture as they please. Political processes of contestation regarding the meaning of and relationships between symbols will determine whether or not change in strategic culture takes place. Strategic culture therefore represents an inherently dynamic structure that is repeatedly reconstituted through the very practices that it enables and constrains. Thus, second-generation strategic culture theory suggests that the existence of long-term patterns in the strategic behaviour of states must be investigated rather than assumed.
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Student background and school factors account for a third of the variation in PISA mathematics test scores (R-squared = 0.31)—a large fraction given that we were not able to control for many other factors that are not available in the dataset such as stu- dent’s prior mathematics achievement. When we controlled for student background and school characteristics separately in Models 2 and 3 we found that school contextual factors explain the differences in achievement between the second- and third-plus gen- erations, and student background characteristics explain the differences between first- generation students and their third-plus generation peers. The fully saturated Model 4 suggests that to understand generational differences and achievement, we should look at both group of factors simultaneously. In other words, student background and school context should be regarded as factors that in combination shape the experiences of stu- dents. This confirms the descriptive evidence provided in Table 2 which indicates that school contextual factors were related to student demographics and background by immigrant generation status.
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Persons attending a tertiary institution full-time were excluded. The proportions of those attending ful-time varied markedly according to origins, from 17 per cent for second-generation Greek-Australians to two per cent for other Australian-born, second-generation New Zealand-Australians and second-generation British-Australians (see Table 4.1). Respondents who were unemployed or who were not in the labour force were also excluded. For all the second generation except the British the higher rate of unemployment noted in Chapter 3 (Table 3.16), may be a function of age or education differences. But it may be that some prefer 'better' jobs to mere employment. In other words, they may be unwilling to compromise high occupational aspirations effected by the educational qualifications and/or by their seeking identity or status in the wider community for less prestigious jobs. This view is supported by Young et al. (1983) in their study of transition from school to workforce of some Melbourne youth though, of course, their sample included youth without post-school qualifications. Nonetheless they found that:
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