Search results for "Clima"

Volcanic CO2 flux measurement at Campi Flegrei by tunable diode laser absorption spectroscopy

2014

Near-infrared room-temperature Tunable Diode Lasers (TDL) have recently found increased usage in atmospheric chemistry and air monitoring research, but applications in volcanology are still limited to a few examples. Here, we explored the potential of a commercial infrared laser unit (GasFinder 2.0 from Boreal Laser Ltd) for measurement of volcanic CO2 mixing ratios, and ultimately for estimating the volcanic CO2 flux. Our field tests were conducted at Campi Flegrei near Pozzuoli, Southern Italy, where the GasFinder was used during three campaigns in October 2012, January 2013 and May 2013 to repeatedly measure the path-integrated mixing ratios of CO2 along cross-sections of the atmospheric…

Signals and memory in tree-ring width and density data

2015

It has been suggested that maximum latewood density (MXD) should be used instead of tree-ring width (TRW) data to reconstruct post-volcanic cooling effects. A thorough assessment of high frequency signals and potentially differing memory effects in long MXD and TRW chronologies, in response to large volcanic eruptions, is still missing, however. We here present a compilation of MXD and TRW chronologies from 11 sites in the Northern Hemisphere, covering the past 750+ years, and containing significant June–August temperature signals. Basic assessment of the data using Superposed Epoch Analysis reveals a temporally extended response in TRW, by 2–3 years, to large volcanic eruptions, though pos…

2017

Abstract. The aim of this study is to present a framework that provides new ways to characterize the spatio-temporal variability of lateral exchanges for water flow and solute transport in a karst conduit network during flood events, treating both the diffusive wave equation and the advection–diffusion equation with the same mathematical approach, assuming uniform lateral flow and solute transport. A solution to the inverse problem for the advection–diffusion equations is then applied to data from two successive gauging stations to simulate flows and solute exchange dynamics after recharge. The study site is the karst conduit network of the Fourbanne aquifer in the French Jura Mountains, wh…

Growth impacts in a changing ocean: insights from two coral reef fishes in an extreme environment

2020

AbstractDetermining the life history consequences for fishes living in extreme and variable environments will be vital in predicting the likely impacts of ongoing climate change on reef fish demography. Here, we compare size-at-age and maximum body size of two common reef fish species (Lutjanus ehrenbergiiandPomacanthus maculosus) between the environmentally extreme Arabian/Persian Gulf (‘Arabian Gulf’) and adjacent comparably benign Oman Sea. Additionally, we use otolith increment width profiles to investigate the influence of temperature, salinity and productivity on the individual growth rates. Individuals of both species showed smaller size-at-age and lower maximum size in the Arabian G…

Interspecific-Competition Strongly Constrains Species-Richness and Species-Abundance Evenness in a Tropical Marine Molluscan Community Inhabiting Cau…

2021

Increasing species-richness at the local scale (within species communities) is accommodated, first, by the diversification of the niches respectively associated to species. Yet, in case of excessive supply in colonizing species issued from the regional pool, the corresponding increase in the number of solicited niches may lead to some “niche-overcrowding” resulting in significant niche-overlaps. Then, second, strong interspecific competition for shared resource can arise, triggered by the density in individuals among those species co-occurring at niche-overlaps. Accordingly, the accommodation of species-richness within a local community involves a balance between (i) the positive contributi…

Late Miocene sea surface salinity variability and paleoclimate conditions in the Eastern Mediterranean inferred from coral aragonite δ18O

2009

Abstract Coral skeletons are archives of chemical proxies which enable paleoenvironmental reconstructions to be made at subannual resolution. Stable oxygen isotope ( δ 18 O) ratios of these archives reflect sea surface temperature (SST) as well as the δ 18 O composition of ambient seawater. The δ 18 O seawater composition is not only controlled by global ice build-up, but river discharge and the hydrological balance of evaporation and precipitation, all influencing sea surface salinity (SSS), also play an important role in marginal seas. New sub-annually resolved coral δ 18 O data were measured and evaluated together with published data from reef coral communities of Late Miocene age from C…

Tourism resources and their development in Maldive Islands

1985

Maldive Islands are characterized by a unique coral nature and thus they posses unique tourism resources though in a one-sided way, namely in the submarine and littoral environment of the islands, lagoons and reefs, associated with the year-round tropical climate. Therefore, not only divers and snorklers enjoy the profuse underwater resources, but also ‘beach tourists’ are attracted by the nature of the beaches and the climatic conditions as well. This environment really guarantees relaxation and recreation. Tourism in Maldives which was introduced in 1972 only, has successfully developed so far. Proof is given by the rapidly growing number of tourists and tourist ‘resorts’ (islands) over t…

Pattern Classification from Multi-beam Acoustic Data Acquired in Kongsfjorden

2021

Climate change is causing a structural change in Arctic ecosystems, decreasing the effectiveness that the polar regions have in cooling water masses, with inevitable repercussions on the climate and with an impact on marine biodiversity. The Svalbard islands under study are an area greatly influenced by Atlantic waters. This area is undergoing changes that are modifying the composition and distribution of the species present. The aim of this work is to provide a method for the classification of acoustic patterns acquired in the Kongsfjorden, Svalbard, Arctic Circle using multibeam technology. Therefore the general objective is the implementation of a methodology useful for identifying the a…

Erratum to “Lamination of swamp-rivulets Rivularia haematites stromatolites in a temperate climate” [Sediment. Geol. 143 (2001) 125–147]

2002

Vulcamera: a program for measuring volcanic SO2 using UV cameras

2011

We report here on Vulcamera, a stand-alone program for the determination of volcanic SO2  fluxes using ultraviolet cameras. The code enables field image acquisition and all the required post-processing operations.<br />