23 research outputs found
Penetration of ultravioletâB radiation in oligotrophic regions of the oceans during the Malaspina 2010 expedition
Few studies have investigated ultraviolet (UV) radiation in the open ocean besides its harmful effects on organisms and influence on biogeochemical processes. Here, we assessed UV attenuation, with particular focus on UVâB, across the (sub)tropical ocean during the Malaspina 2010 Circumnavigation. Vertical UV radiometer profiles together with Chlâ
a
concentration, and UV absorption by CDOM (
a
CDOM
(
λ
)) and by suspended particulate matter (
a
p
(
λ
)) were measured at 117 stations. At photosynthetically active radiation (PAR) and across UVâA and UVâB wavelengths, the lowest downwelling attenuation coefficients (
K
d
) during the expedition were recorded in ultraâoligotrophic regions at 5°â15°S (mean
K
d
(305Â nm): 0.129Â m
â1
, mean
K
d
(313Â nm): 0.107Â m
â1
) in the Indian and South Pacific Oceans. The waters here were comparatively more transparent than at 5°â15°N (mean
K
d
(305Â nm): 0.239Â m
â1
, mean
K
d
(313Â nm): 0.181Â m
â1
) where equatorial upwelling occurs.
K
d
was highest near the Costa Rica Dome (
K
d
(313Â nm): 0.226Â m
â1
) and at the confluence of the Benguela and Agulhas currents (
K
d
(313Â nm): 0.251Â m
â1
). The contribution of
a
p
(
λ
) toward nonwater absorption (
a
nw
(
λ
)) was significantly lower at 305Â nm than at 313 and 320Â nm, suggesting the contribution of absorption by detritus and phytoplankton particles decreases compared with that of CDOM absorption as UVâB wavelength decreases. Both
a
CDOM
(
λ
) and
a
p
(
λ
) at UVâB wavelengths were lowest in the Indian Ocean whereas
K
d
was lowest in the South Pacific. This finding emphasizes that other factors besides absorption, such as scattering by reflective phytoplankton or inorganic particles, strongly influence UVâB attenuation in open ocean waters.Plain Language Summary: We assessed water transparency to UVâB radiation across the tropical and subtropical ocean as part of the Malaspina 2010 Expedition. UVâB radiometer profiles, Chlorophyllâa, and UVâB absorption by organic matter and suspended particles were measured at 117 stations. The most UVâB transparent waters were found in regions where nutrients are extremely low, particularly at 5°â15°S in the Indian and South Pacific Oceans. Here, ocean waters were considerably more transparent than 5°â15°N, which suggests that at a given depth southern hemisphere marine organisms experience higher UVâB exposure than their northern counterparts. The least UVâB transparent waters were near the Costa Rica Dome and at the confluence of the Benguela and Agulhas currents. UVâB absorption by organic matter and suspended particles, and Chlâ
a
concentration were lowest in the Indian Ocean. The contribution of suspended particles toward nonwater absorption was significantly lower at 305Â nm than at 313 and 320Â nm, and higher in the clearest waters of the Indian Ocean than in the Subtropical South Pacific. Absorptions by organic matter and suspended particles were lowest in the Indian Ocean whereas UVâB attenuation was lowest in the South Pacific, which highlights the complex relationship between optical properties in the UVâB spectrum.Ministerio de Ciencia e InnovaciĂłn | Ref. CSD2008-00077King Abdullah University of Science and Technology | Ref. BAS/1/1072-01-0
Where Nothing Happened: The Experience of War Captivity and Levinasâs Concept of the âThere Isâ
This article takes as its subject matter the juridico-political space of the prisoner of war (POW) camp. It sets out to determine the nature of this space by looking at the experience of war captivity by Jewish members of the Western forces in World War II, focusing on the experience of Emmanuel Levinas, who spent 5 years in German war captivity. On the basis of a historical analysis of the conditions in which Levinas spent his time in captivity, it argues that the POW camp was a space of indifference that was determined by the legal exclusion of prisoners from both war and persecution. Held behind the stage of world events, prisoners were neither able to exercise their legal agency nor released from law into a realm of extra-legal violence. Through a close reading of Levinasâs early concept of the âthere isâ [il y a], the article seeks to establish the impact on prisoners of prolonged confinement in such a space. It sets out how prisonersâ subjectivity dissolved in the absence of meaningful relations with others and identifies the POW camp as a space in which existence was reduced to indeterminate, impersonal being
Data set accompanying the article: Unraveling the Seasonality of UV Exposure in Reef Waters of a Rapidly Warming (Sub-)tropical Sea
This data set comprises of the underlying data used in Figures 2 (incident UV), 3 & 6 (Temperature, Chl-a and aCDOM), 4 (Kd), 5 (in situ UV exposure) and 7 (projected temperature and UV-B) of the publication entitled "Unraveling the Seasonality of UV Exposure in Reef Waters of a Rapidly Warming (Sub-)tropical Sea".
Keywords: Red Sea, coral reefs, marine optics, ultraviolet radiation (UV), daily UV exposure, downwelling diffuse attenuation coefficient (Kd), chlorophyll-a, CDOM, temperature, seasonality, climate chang
Data set accompanying the article: Unraveling the Seasonality of UV Exposure in Reef Waters of a Rapidly Warming (Sub-)tropical Sea
This data set comprises of the underlying data used in Figures 2 (incident UV), 3 & 6 (Temperature, Chl-a and aCDOM), 4 (Kd), 5 (in situ UV exposure) and 7 (projected temperature and UV-B) of the publication entitled "Unraveling the Seasonality of UV Exposure in Reef Waters of a Rapidly Warming (Sub-)tropical Sea".
Keywords: Red Sea, coral reefs, marine optics, ultraviolet radiation (UV), daily UV exposure, downwelling diffuse attenuation coefficient (Kd), chlorophyll-a, CDOM, temperature, seasonality, climate chang
MALASPINA 2010 optical data: aCDOM_aParticles_Kd_Z10%
The dataset is comprised of: downwelling diffuse attenuation coefficients, Z10%, aCDOM and apTHIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV
The effect of simulations and games on learning objectives in tertiary education : A systematic review
The growing popularity of simulations and games invites the production of insights that help academic teachers to use simulations and games in their courses. This article clarifies positive conditions to use simulations and games in tertiary education. Based on a systematic review of literature we tentatively find a positive or neutral relationship between using simulations and games and achieving learning objectives. Also, we find three recurring conditions for successful use of simulations and games: the specificity of the game, the integration in the course, and the role of a guiding instructor. Finally, we express the strong need for a scientific framework to measure effectiveness of simulations and games
Penetration of Ultraviolet-B Radiation in Oligotrophic Regions of the Oceans During the Malaspina 2010 Expedition
21 pages, 4 tables, 8 figures.-- This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs LicenseFew studies have investigated ultraviolet (UV) radiation in the open ocean besides its harmful effects on organisms and influence on biogeochemical processes. Here, we assessed UV attenuation, with particular focus on UV-B, across the (sub)tropical ocean during the Malaspina 2010 Circumnavigation. Vertical UV radiometer profiles together with Chl-a concentration, and UV absorption by CDOM (aCDOM(λ)) and by suspended particulate matter (ap(λ)) were measured at 117 stations. At photosynthetically active radiation (PAR) and across UV-A and UV-B wavelengths, the lowest downwelling attenuation coefficients (Kd) during the expedition were recorded in ultra-oligotrophic regions at 5°â15°S (mean Kd(305 nm): 0.129 mâ1, mean Kd(313 nm): 0.107 mâ1) in the Indian and South Pacific Oceans. The waters here were comparatively more transparent than at 5°â15°N (mean Kd(305 nm): 0.239 mâ1, mean Kd(313 nm): 0.181 mâ1) where equatorial upwelling occurs. Kd was highest near the Costa Rica Dome (Kd(313 nm): 0.226 mâ1) and at the confluence of the Benguela and Agulhas currents (Kd(313 nm): 0.251 mâ1). The contribution of ap(λ) toward nonwater absorption (anw(λ)) was significantly lower at 305 nm than at 313 and 320 nm, suggesting the contribution of absorption by detritus and phytoplankton particles decreases compared with that of CDOM absorption as UV-B wavelength decreases. Both aCDOM(λ) and ap(λ) at UV-B wavelengths were lowest in the Indian Ocean whereas Kd was lowest in the South Pacific. This finding emphasizes that other factors besides absorption, such as scattering by reflective phytoplankton or inorganic particles, strongly influence UV-B attenuation in open ocean watersThis study was funded by the Spanish Ministry of Economy and Competitiveness through the Malaspina 2010 Expedition project (Consolider-Ingenio 2010; MICINN CSD2008-00077). The PhD fellowship of SO was supported by the baseline funding from KAUST to S. AgustĂ under award number BAS/1/1072-01-01Peer reviewe
MALASPINA 2010 optical data: aCDOM_aParticles_Kd_Z10%
The dataset is comprised of: downwelling diffuse attenuation coefficients, Z10%, aCDOM and ap.Peer reviewe
MALASPINA 2010 optical data: aCDOM_aParticles_Kd_Z10%
The dataset is comprised of: downwelling diffuse attenuation coefficients, Z10%, aCDOM and apPeer reviewe