Dataset Information

View angle dependence of MODIS liquid water path retrievals in warm oceanic clouds.

ABSTRACT: We investigated the view angle dependence of domain mean Moderate Resolution Imaging Spectroradiometer (MODIS) liquid water path (LWP) and that of corresponding cloud optical thickness, effective radius, and liquid cloud fraction as proxy for plane-parallel retrieval biases. Independent Advanced Microwave Scanning Radiometer-EOS LWP was used to corroborate that the observed variations with sun-view geometry were not severely affected by seasonal/latitudinal changes in cloud properties. Microwave retrievals showed generally small (<10%) cross-swath variations. The view angle (cross-swath) dependence of MODIS optical thickness was weaker in backscatter than forward scatter directions and transitioned from mild ? shape to stronger ? shape as heterogeneity, sun angle, or latitude increased. The 2.2 µm effective radius variations always had a ? shape, which became pronounced and asymmetric toward forward scatter in the most heterogeneous clouds and/or at the lowest sun. Cloud fraction had the strongest and always ?-shaped view angle dependence. As a result, in-cloud MODIS cloud liquid water path (CLWP) showed surprisingly good view angle (cross-swath) consistency, usually comparable to that of microwave retrievals, due to cancelation between optical thickness and effective radius biases. Larger (20-40%) nadir-relative increases were observed in the most extreme heterogeneity and sun angle bins, that is, typically in the polar regions, which, however, constituted only 3-8% of retrievals. The good consistency of MODIS in-cloud CLWP was lost for gridbox mean LWP, which was dominated by the strong cloud fraction increase with view angle. More worryingly, MODIS LWP exhibited significant and systematic absolute increases with heterogeneity and sun angle that is not present in microwave LWP.

Key points

Microwave LWP shows small overall and cross-swath variationsMODIS in-cloud LWP also shows good view angle consistency in most casesMODIS retrievals show strong overall increase with heterogeneity and sun angle.

SUBMITTER: Horvath A

PROVIDER: S-EPMC4370763 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Publications

View angle dependence of MODIS liquid water path retrievals in warm oceanic clouds.

Horváth Ákos Á Seethala Chellappan C Deneke Hartwig H

Journal of geophysical research. Atmospheres : JGR 20140712 13

We investigated the view angle dependence of domain mean Moderate Resolution Imaging Spectroradiometer (MODIS) liquid water path (LWP) and that of corresponding cloud optical thickness, effective radius, and liquid cloud fraction as proxy for plane-parallel retrieval biases. Independent Advanced Microwave Scanning Radiometer-EOS LWP was used to corroborate that the observed variations with sun-view geometry were not severely affected by seasonal/latitudinal changes in cloud properties. Microwave ...[more]

PMID: 25821665

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Project description:The body of literature on entrepreneurial ecosystems (EEs) is rapidly expanding, but few studies have simultaneously examined their complexity, dynamics, and context. To better understand how they evolve, we introduce the notion of EE path dependence based on an original combination of an evolutionary approach and complex adaptive system theory. We thus present a whirlwind model that takes the form of subecosystems and that integrates a structural approach with attributes and a dynamic approach with sequences. Context is addressed through narratives and entrepreneurial stories. We conducted a case study on the EE of Montpellier, France. To characterize the subecosystems, we quantified the attributes using NVivo software, showing their links and evolution over time. The results shed light on the subecosystems that contributed the most to the entrepreneurial dynamics. This study contributes to extending path dependence theory to EEs. The results may help policymakers rethink their development strategies by setting priorities in accordance with the drivers of their EEs. Supplementary Information The online version contains supplementary material available at 10.1007/s11187-021-00553-x. Plain English Summary We propose a whirlwind model of entrepreneurial ecosystem (EE) path dependence to comprehensively explore the complex, dynamic and contextual nature of an EE. Based on the narratives of EE actors and entrepreneurial stories from a specific region, we identify significant attributes and decompose the ecosystem into subecosystems. The dynamics are understood through the links between the attributes and their evolution over time. This work allows us to characterize the specific aspects of the EE and to identify the drivers of this evolution. The subecosystems operate like EE markers according to a logic of coevolution. This detailed understanding of the trajectory constitutes a strategic asset for projecting into the future with the ability to identify development priorities for EE stakeholders. Supplementary Information The online version contains supplementary material available at 10.1007/s11187-021-00553-x.

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Dataset Information

View angle dependence of MODIS liquid water path retrievals in warm oceanic clouds.

Key points

Publications

View angle dependence of MODIS liquid water path retrievals in warm oceanic clouds.

Similar Datasets

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