Temporal variations of cryoconite holes and cryoconite coverage on the ablation ice surface of Qaanaaq Glacier in northwest Greenland

AbstractCryoconite holes are water-filled cylindrical holes formed on ablation ice surfaces and commonly observed on glaciers worldwide. Temporal changes of cryoconite holes characteristically <5 cm in diameter were monitored with a time-lapse interval camera over 15 d during the melting season on Qaanaaq Glacier in northwest Greenland. The holes drastically changed their dimensions and synchronously collapsed twice during the study period. When the holes collapsed, the coverage of cryoconite on the ice surface increased from 1.0 to 3.5% in the field of view of the camera, and then decreased again to 0.4% after the holes reformed. Comparison with meteorological data showed that the collapses occurred in cloudy and rainy or windy weather conditions, corresponding to low shortwave solar radiation (68–126 W m−2, 40–55% of the incoming flux). In contrast, holes developed in sunny conditions correspond to high solar radiation (186–278 W m−2, 63–88%). Results suggest that the dimensions of holes drastically changed depending on the weather conditions and that frequent cloudy, warm and windy conditions would cause a decay of holes and weathering crust, inducing an increase in the cryoconite coverage on the ice, consequently darkening the glacier surface.

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Destruction of chlorophyll in emerging seedlings of spring barley associated with environmental stresses

Plant Protection Science ◽

10.17221/2752-pps ◽

2010 ◽

Vol 41 (No. 4) ◽

pp. 165-170 ◽

Cited By ~ 1

Author(s):

V. Kůdela ◽

B. Voženílková ◽

R. Krejzarová ◽

V. Krejzar ◽

M. Janouch

Keyword(s):

Solar Radiation ◽

Meteorological Data ◽

Spring Barley ◽

Environmental Stresses ◽

Plant Tissues ◽

Chronological Order ◽

Uv Index ◽

High Solar Radiation

An unusual disorder occurred on spring barley seedlings in southern and central Bohemia in April 2005. Affected seedlings showed conspicuous bleached or straw-coloured areas on tips of the first leaves. There were very sharp, distinct, horizontal boundaries between the green basal and discoloured tip parts of the leaves. It was remarkable that these boundaries were at the same position on all affected first leaves of seedlings from the same field. Affected seedlings were randomly distributed in the fields, and their incidence ranged from about 20 to 70% according to location. Based on meteorological data it can be concluded that the colour abnormality in emerging seedlings was associated with specific environmental stresses, being effective in certain chronological order on sensitive plant tissues during the period from 6 to 8 days after seeding. These stresses include frosty mornings followed by clear days with high solar radiation with a high UV Index.

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Impact of climatic conditions on fumonisins in maize grown in Serbia

World Mycotoxin Journal ◽

10.3920/wmj2018.2364 ◽

2019 ◽

Vol 12 (2) ◽

pp. 183-190 ◽

Cited By ~ 3

Author(s):

B. Udovicki ◽

I. Djekic ◽

S. Stankovic ◽

A. Obradovic ◽

A. Rajkovic

Keyword(s):

Solar Radiation ◽

Critical Parameter ◽

Meteorological Data ◽

Climatic Conditions ◽

Chi Square ◽

High Solar Radiation ◽

Significant Difference ◽

Chi Square Test ◽

Low Humidity ◽

Low Precipitation

The influence of climatic conditions on the levels of fumonisins in maize grown in Serbia was studied over eight years (2008 to 2015), investigating the possible relationship between the levels of fumonisins contamination in maize in relation to registered weather/climatic conditions. Presence of these mycotoxins in maize after harvest was evaluated based on climatic conditions within two periods: 10 days before and 10 days after 50% silking. Categories of fumonisins levels were transformed into classes. Chi-square test for association was used in analysing relationships between results of fumonisins levels and calendar years. Mann-Whitney U-test was used to compare differences between meteorological data of two subsets in years with high and low fumonisins level. There was a statistically significant association between the fumonisins levels and calendar years χ2=247.954; (P<0.05). This study identified low precipitation and low humidity combined with high solar radiation as a critical parameter combination for elevated levels of fumonisins. The statistically significant difference in relation to some of the examined parameters suggests that maize in Serbian agro-climatic conditions is more susceptible to fungal colonisation, and subsequent fumonisin production in the period of 10 days before 50% silking.

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Estimating spatial and temporal variations in solar radiation within Bordeaux winegrowing region using remotely sensed data

OENO One ◽

10.20870/oeno-one.2008.42.1.829 ◽

2008 ◽

Vol 42 (1) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

Benjamin Bois ◽

Lucien Wald ◽

Philippe Pieri ◽

Cornelis Van Leeuwen ◽

Loïc Commagnac ◽

...

Keyword(s):

Solar Radiation ◽

Temporal Variations ◽

Spatial And Temporal Variations ◽

Remotely Sensed Data ◽

High Solar Radiation ◽

Daily Data ◽

Digital Elevation ◽

Terrain Effect ◽

Resolution Mapping ◽

Elevation Model

Aims: This paper presents a study of spatial and temporal variations in solar radiation for the Bordeaux winegrowing region, over a 20 year period (1986-2005).Methods and results: Solar radiation data was retrieved from the HelioClim-1 database, elaborated from Meteosat satellite images, using the Heliosat-2 algorithm. Daily data was interpolated using ordinary kriging to produce horizontal solar radiation maps at a 500 m resolution. Then using a digital elevation model, 50 m resolution daily solar radiation maps with terrain integration were produced for the period 2001-2005. The long term (20 year) analysis of solar radiation at low spatial resolution (500 m) showed a west to east decreasing gradient within the Bordeaux winegrowing region. Mean August-to-September daily irradiation values, on horizontal surface, were used to classify the Bordeaux winegrowing region into three zones: low, medium, and high solar radiation areas. This initial zoning was downscaled to 50 m resolution, applying a local correction ratio, based on 2001-2005 solar radiation from the inclined surface analysis. Grapevine development and maturation potential of the different zones of appellation of origin of Bordeaux winegrowing regions are discussed in relation with this zoning.Conclusion: Solar radiation variability within the Bordeaux winegrowing region is mainly governed by terrain slopes and orientations, which induce considerable variations within the eastern part of Bordeaux vineyards. Significance and impact of study: Solar radiation has a major impact on vineyard water balance, grapevine development and berry ripening. However, irradiation data is seldom available in weather stations records. This paper highlights the need for high resolution mapping of solar radiation that uses remote sensing and terrain effect integration for agroclimatic studies in viticulture.

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Measuring glacier surface roughness using plot-scale, close-range digital photogrammetry

Journal of Glaciology ◽

10.3189/2014jog14j032 ◽

2014 ◽

Vol 60 (223) ◽

pp. 957-969 ◽

Cited By ~ 21

Author(s):

Tristram D.L. Irvine-Fynn ◽

Enoc Sanz-Ablanedo ◽

Nick Rutter ◽

Mark W. Smith ◽

Jim H. Chandler

Keyword(s):

Surface Roughness ◽

Temporal Variations ◽

Horizontal Resolution ◽

Spatial And Temporal Variation ◽

Stereo Pair ◽

Digital Photogrammetry ◽

Glacier Surface ◽

Ice Surface ◽

Close Range ◽

Ice Surface Roughness

AbstractGlacier roughness at sub-metre scales is an important control on the ice surface energy balance and has implications for scattering energy measured by remote-sensing instruments. Ice surface roughness is dynamic as a consequence of spatial and temporal variation in ablation. To date, studies relying on singular and/or spatially discrete two-dimensional profiles to describe ice surface roughness have failed to resolve common patterns or causes of variation in glacier surface morphology. Here we demonstrate the potential of close-range digital photogrammetry as a rapid and cost-effective method to retrieve three-dimensional data detailing plot-scale supraglacial topography. The photogrammetric approach here employed a calibrated, consumer-grade 5 Mpix digital camera repeatedly imaging a plot-scale (≤25 m2) ice surface area on Midtre Lovénbreen, Svalbard. From stereo-pair images, digital surface models (DSMs) with sub-centimetre horizontal resolution and 3 mm vertical precision were achieved at plot scales ≤4 m2. Extraction of roughness metrics including estimates of aerodynamic roughness length (z0) was readily achievable, and temporal variations in the glacier surface topography were captured. Close-range photogrammetry, with appropriate camera calibration and image acquisition geometry, is shown to be a robust method to record sub-centimetre variations in ablating ice topography. While the DSM plot area may be limited through use of stereo-pair images and issues of obliquity, emerging photogrammetric packages are likely to overcome such limitations.

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SOLAR RADIATION MODEL FOR DEVELOPMENT AND CONTROL OF SOLAR ENERGY SOURCES / SAULĖS SPINDULIAVIMO MODELIS FOTOVOLTINIŲ ELEKTRINIŲ PROJEKTAVIMUI IR VALDYMUI

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2016.932 ◽

2016 ◽

Vol 8 (3) ◽

pp. 289-295

Author(s):

Dominykas Vasarevičius ◽

Modestas Pikutis

Keyword(s):

Solar Radiation ◽

Solar Energy ◽

Meteorological Data ◽

Weather Conditions ◽

Cloud Layer ◽

Total Solar Radiation ◽

Radiation Model ◽

Point Tracking ◽

Solar Radiation Model ◽

Power Point

The model of solar radiation, which takes into account direct, diffused and reflected components of solar energy, has been presented. Model is associated with geographical coordinates and local time of every day of the year. It is shown that using analytic equations for modelling the direct component, it is possible to adopt it for embedded systems with low computational power and use in solar tracking applications. Reflected and diffused components are especially useful in determining the performance of photovoltaic modules in certain location and surroundings. The statistical method for cloud layer simulation based on local meteorological data is offered. The presented method can’t be used for prediction of weather conditions but it provides patterns of solar radiation in time comparable to those measured with pyranometer. Cloud layer simulation together with total solar radiation model is a useful tool for development and analysis of maximum power point tracking controllers for PV modules. Pateikiamą saulės spinduliavimo modelį sudaro trys komponentai: tiesioginio spinduliavimo, sklaidos ir atspindžių. Modelyje numatyta galimybė jį susieti su fotovoltinės elektrinės vietovės geografinėmis koordinatėmis, metų diena ir vietos laiku. Modelio komponentuose panaudotos analitinės formulės nereikalauja didelių skaičiavimo resursų. Tai leidžia modelį taikyti didžiausios galios taško sekimui skirtose įterptinėse sistemose. Sklaidos ir atspindžių komponentai leidžia nustatyti fotovoltinių modulių efektyvumą elektrinės įrengimo vietovėje. Debesų modelis sudarytas remiantis gaunamais statistiniais meteorologiniais duomenimis. Pateiktas modelis negali būti naudojamas oro sąlygų prognozei. Modeliu imituojamas saulės spinduliavimas atkartoja rezultatus, gautus matuojant piranometru. Saulės spinduliavimo modelis, įvertinantis dangaus debesuotumą, yra naudingas įrankis kuriant fotovoltinių modulių didžiausios galios sekimo elektronines sistemas.

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Rain Erosion Maps for Wind Turbines Based on Geographical Locations: A Case Study in Ireland and Britain

Journal of Bio- and Tribo-Corrosion ◽

10.1007/s40735-021-00472-0 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

K. Pugh ◽

M. M. Stack

Keyword(s):

Wind Turbine ◽

Western Europe ◽

Meteorological Data ◽

Turbine Blades ◽

Weather Conditions ◽

Annual Rainfall ◽

Wind Turbine Blades ◽

Weather Patterns ◽

The Uk

AbstractErosion rates of wind turbine blades are not constant, and they depend on many external factors including meteorological differences relating to global weather patterns. In order to track the degradation of the turbine blades, it is important to analyse the distribution and change in weather conditions across the country. This case study addresses rainfall in Western Europe using the UK and Ireland data to create a relationship between the erosion rate of wind turbine blades and rainfall for both countries. In order to match the appropriate erosion data to the meteorological data, 2 months of the annual rainfall were chosen, and the differences were analysed. The month of highest rain, January and month of least rain, May were selected for the study. The two variables were then combined with other data including hailstorm events and locations of wind turbine farms to create a general overview of erosion with relation to wind turbine blades.

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Utilising Open Geospatial Data to Refine Weather Variables for Building Energy Performance Evaluation—Incident Solar Radiation and Wind-Driven Infiltration Modelling

Energies ◽

10.3390/en14040802 ◽

2021 ◽

Vol 14 (4) ◽

pp. 802

Author(s):

Kristian Skeie ◽

Arild Gustavsen

Keyword(s):

Solar Radiation ◽

Web Service ◽

Meteorological Data ◽

Surface Wind ◽

Building Energy ◽

Energy Performance ◽

Geospatial Data ◽

Weather Data ◽

Building Site ◽

Incident Solar Radiation

In building thermal energy characterisation, the relevance of proper modelling of the effects caused by solar radiation, temperature and wind is seen as a critical factor. Open geospatial datasets are growing in diversity, easing access to meteorological data and other relevant information that can be used for building energy modelling. However, the application of geospatial techniques combining multiple open datasets is not yet common in the often scripted workflows of data-driven building thermal performance characterisation. We present a method for processing time-series from climate reanalysis and satellite-derived solar irradiance services, by implementing land-use, and elevation raster maps served in an elevation profile web-service. The article describes a methodology to: (1) adapt gridded weather data to four case-building sites in Europe; (2) calculate the incident solar radiation on the building facades; (3) estimate wind and temperature-dependent infiltration using a single-zone infiltration model and (4) including separating and evaluating the sheltering effect of buildings and trees in the vicinity, based on building footprints. Calculations of solar radiation, surface wind and air infiltration potential are done using validated models published in the scientific literature. We found that using scripting tools to automate geoprocessing tasks is widespread, and implementing such techniques in conjunction with an elevation profile web service made it possible to utilise information from open geospatial data surrounding a building site effectively. We expect that the modelling approach could be further improved, including diffuse-shading methods and evaluating other wind shelter methods for urban settings.

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A Whole-Field Interferometric Scheme for Measuring strain and Flow Rates of Glacier and Other Natural Surfaces

Journal of Glaciology ◽

10.3189/s0022143000030392 ◽

1983 ◽

Vol 29 (103) ◽

pp. 492-497

Author(s):

Gary Cloud ◽

Edgar Conley

Keyword(s):

Displacement Vector ◽

Surface Displacement ◽

Time Lapse ◽

Speckle Interferometry ◽

Narrow Beam ◽

Coherent Light ◽

Ice Surface ◽

Glacier Ice ◽

Fringe Patterns ◽

Small Overlap

AbstractThe flow of glacier ice is mapped using high-resolution photography and non-coherent-light speckle interferometry. Young’s fringe patterns result when a double-exposed photoplate image of the straining surface is illuminated by a narrow beam of coherent light. Geometry gives a relationship between the ice surface displacement vector and the interference fringe patterns. This displacement vector is corrected for rigid-body (camera) movement and projected onto the ice surface using topological maps. The strain during the time-lapse interval is thus known. Comparison with data acquired by surveying techniques at Nisqually Glacier, Washington, U.S.A., is limited because of small overlap of the surface studied. In the areas for which results can be compared, our experiments yield a flow of 0.6 m/d where conventional methods yield about 0.4 m/d.

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Estimation of the total solar radiation from meteorological data

Solar Energy ◽

10.1016/0038-092x(77)90075-5 ◽

1977 ◽

Vol 19 (3) ◽

pp. 307-311 ◽

Cited By ~ 110

Author(s):

J.A. Sabbagh ◽

A.A.M. Sayigh ◽

E.M.A. El-Salam

Keyword(s):

Solar Radiation ◽

Meteorological Data ◽

Total Solar Radiation

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Statistical Analysis of Weather Effects on PM2.5

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.1033 ◽

2012 ◽

Vol 610-613 ◽

pp. 1033-1040

Author(s):

Wei Dai ◽

Jia Qi Gao ◽

Bo Wang ◽

Feng Ouyang

Keyword(s):

Statistical Analysis ◽

Wind Speed ◽

Relative Humidity ◽

Statistical Methods ◽

Predictive Analytics ◽

Hypothesis Test ◽

Meteorological Data ◽

Weather Conditions ◽

Statistical Distribution ◽

Weather Effects

Effects of weather conditions including temperature, relative humidity, wind speed, wind and direction on PM2.5 were studied using statistical methods. PM2.5 samples were collected during the summer and the winter in a suburb of Shenzhen. Then, correlations, hypothesis test and statistical distribution of PM2.5 and meteorological data were analyzed with IBM SPSS predictive analytics software. Seasonal and daily variations of PM2.5 have been found and these mainly resulted from the weather effects.

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