Best practices for surface radiation observations from long-term moored buoys

2020 ◽  
Author(s):  
Robert Weller ◽  
J. Thomas Farrar ◽  
Sebastien Bigorre ◽  
Jason Smith ◽  
James Potemra ◽  
...  
Keyword(s):  
Field Experiments ◽  
Surface Radiation ◽  
Tropical Atlantic ◽  
Woods Hole Oceanographic Institution ◽  
Stratus Clouds ◽  
Radiation Data ◽  
Marine Stratus ◽  
One Year ◽  
Process Group

<p>The Upper Ocean Process Group of the Woods Hole Oceanographic Institution deploys moorings with surface buoys instrumented with incoming shortwave and longwave radiometers at locations around the world.  The procedures used to calibrate the radiometers in the laboratory and to assess their performance at sea are discussed.  Some mooring deployments are done during collaborative field experiments and are months to a year in length.  Three other sites are being maintained as long-term Ocean Reference Stations (ORS), with sequential one-year deployments being used to collect ongoing time series.  The Stratus ORS, located under the marine stratus clouds off northern Chile, has been collecting surface radiation observations since 2000.  The NTAS ORS in the western tropical Atlantic has collected surface radiation data since 2001; and the WHOTS ORS north of island of Oahu, Hawaii has collected surface radiation data since 2004.  Challenges encountered in making the surface radiation observations are discussed, and the best estimates of observational uncertainties are presented.  With this understanding of the accuracies of the observations, comparisons between the buoy observations and surface radiation values from models and reanalyses are shown.  Work underway on further improvements to the approaches taken to make surface radiation observations from moored buoy are discussed, and a suggestion for field intercomparisons with other oceanic and land-based surface radiation observing platforms is put forward.</p>

scholarly journals 15N-Tracertechnik in der Pflanzenbauforschung

2001 ◽  
pp. 3-9
Author(s):  
Heinz Peschke
Keyword(s):  
Laboratory Experiments ◽  
Field Experiments ◽  
15N Tracer ◽  
Chemical Research ◽  
N Dynamics ◽  
Research Designs ◽  
Term Trial ◽  
One Year ◽  
The Given

Issues of nitrogen are still of particular importance in crop sciences. 15N-tracer are used to identify the N dynamics in soils and the N transfer between soil and plant. This tool is also helpful in clarifying fertilization problems.This article points out the special requirements for the application of stable 15N-isotops in agri-chemical research. Designs and results of selected laboratory experiments, examples of one-year field experiments, and a 15N long-term trial are represented in detail. The given literature refers to detailed results of diverse 15N publications in the system soil – fertilizer – (animal) – crop.

scholarly journals Performance and Uncertainty of CNR1 Net Radiometers during a One-Year Field Comparison

2008 ◽  
Vol 25 (3) ◽  
pp. 442-451 ◽  
Author(s):  
Dominik Michel ◽  
Rolf Philipona ◽  
Christian Ruckstuhl ◽  
Roland Vogt ◽  
Laurent Vuilleumier
Keyword(s):  
Field Experiments ◽  
Longwave Radiation ◽  
High Standard ◽  
Sensitivity Coefficient ◽  
Surface Energy Budget ◽  
Surface Radiation ◽  
Net Radiation ◽  
Field Calibration ◽  
One Year ◽  
The Individual

Abstract Net radiation flux in correlation with surface energy budget, snowmelt, glacier ice balance, and forest or agricultural flux exchange investigations is measured in numerous field experiments. Instrument costs and energy consumption versus performance and uncertainty of net radiation instruments has been widely discussed. Here the authors analyze and show performance and uncertainty of two Kipp and Zonen CNR1 net radiometers, which were compared to high standard reference radiation instruments measuring individual shortwave and longwave downward and upward flux components. The intercomparison was aimed at investigating the performance of the radiometers under different climatological conditions and was made over one year at the midlatitude Baseline Surface Radiation Network (BSRN) station in Payerne, Switzerland (490 MSL). Of the two CNR1 radiometers tested, one was installed in a ventilation and heating system, whereas the other was mounted without ventilation and heating. Uncertainties of the different flux components were found to be larger for shortwave than longwave radiation and larger for downward than upward components. Using the single sensitivity coefficient provided by the manufacturer, which for CNR1 radiometers conditions using all four sensors, rather large root-mean-square differences between 2 and 14 W m−2 were measured for the individual components for hourly averages and between 2 and 12 W m−2 for daily averages. The authors then performed a field calibration, comparing each individual sensor to the reference instrument for one particular day. With the individual field calibration the uncertainty of hourly averages was reduced significantly for all components of the ventilated and heated instrument. For the unventilated CNR1 uncertainties could not be reduced significantly for all sensors. The total net radiation uncertainty of both CNR1 is rather large with up to 26% on daily averages (∼10 W m−2) for the original sensitivity coefficients and without field calibration. Only with the field calibration and for the ventilated and heated CNR1 net radiometer is an uncertainty of 10% of the daily totals of total net radiation reached, as claimed by the manufacturer.

scholarly journals Evaluation of the CERES models in different production regions of the Czech Republic

2011 ◽  
Vol 48 (No. 3) ◽  
pp. 125-132
Author(s):  
M. Šťastná ◽  
M. Trnka ◽  
J. Křen ◽  
M. Dubrovský ◽  
Z. Žalud
Keyword(s):  
Model Evaluation ◽  
Field Experiments ◽  
Coefficient Of Determination ◽  
Wheat Crop ◽  
Crop Models ◽  
Multiple Treatment ◽  
Historical Series ◽  
Treatment Experiment ◽  
One Year

The main goal of this work was to calibrate and evaluate the CERES-Barley and CERES-Wheat crop models. The experimental fields used for the model evaluation are situated in three different production regions (maize, sugar beet and potato main growing regions, respectively) with altitudes of 179, 204 and 560 meters above the sea level. Grain yield and date of anthesis together with maturity dates served as reference for the model evaluation. Two evaluation approaches were tested in this study. The first one uses historical data series and it is based on long-term field experiments with capability to reflect interannual weather variability. The second approach uses results of one-year multiple treatment experiment. The model evaluation is then based on a set of treatments differing e.g. in sowing date or an amount of used nitrogen fertilizer. Grain yields simulated by both models are acceptable when compared with experimental results: the coefficient of determination for historical series varied from 0.69 to 0.86 for evaluation of CERES-Barley at the three examined sites and reached values of 0.60 and 0.86 for the CERES-Wheat model at two experimental sites. The lower coefficient of determination of the wheat model was recorded at the locality with the highest altitude and coldest winter conditions. There, also the worst reliability of simulated phenological development was noted. At the second locality where the CERES-Wheat model was tested and at all three localities where CERES-Barley was applied, the simulated duration of vegetation period and anthesis dates were relatively accurate and yielded strong statistical correlation. The one-year multiple treatment experiment proved to be useful to determine the models sensitivity to differences in crop management. The combination of both approaches seems to be the best solution for evaluation of similar crop models if the detail long term experimental data are not available.

scholarly journals Effects of disk tillage on soil condition, crop yield and weed infestation

2011 ◽  
Vol 48 (No. 1) ◽  
pp. 20-26
Author(s):  
M. Birkás ◽  
T. Szalai ◽  
C. Gyuricza ◽  
M. Gecse ◽  
K. Bordás
Keyword(s):  
Winter Wheat ◽  
Crop Yield ◽  
Field Experiments ◽  
Soil Layer ◽  
Soil Condition ◽  
Perennial Weeds ◽  
Weed Infestation ◽  
Set Up ◽  
Different Levels

This research was instigated by the fact that during the last decade annually repeated shallow disk tillage on the same field became frequent practice in Hungary. In order to study the changes of soil condition associated with disk tillage and to assess it is consequences, long-term tillage field experiments with different levels of nutrients were set up in 1991 (A) and in 1994 (B) on Chromic Luvisol at Gödöllö. The effects of disk tillage (D) and disk tillage combined with loosening (LD) on soil condition, on yield of maize and winter wheat, and on weed infestation were examined. The evaluation of soil condition measured by cone index and bulk density indicated that use of disking annually resulted in a dense soil layer below the disking depth (diskpan-compaction). It was found, that soil condition deteriorated by diskpan-compaction decreased the yield of maize significantly by 20 and 42% (w/w), and that of wheat by 13 and 15% (w/w) when compared to soils with no diskpan-compaction. Averaged over seven years, and three fertilizer levels, the cover % of the total, grass and perennial weeds on loosened soils were 73, 69 and 65% of soils contained diskpan-compaction.

scholarly journals A206 EVOLUTION OF PEDIATRIC AUTOIMMUNE CHOLANGITIS AND PRIMARY SCLEROSING CHOLANGITIS INTO ADULTHOOD

2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 234-236
Author(s):  
P Willems ◽  
J Hercun ◽  
C Vincent ◽  
F Alvarez
Keyword(s):  
Primary Sclerosing Cholangitis ◽  
Sclerosing Cholangitis ◽  
Response To Treatment ◽  
Similar Proportion ◽  
Autoimmune Cholangitis ◽  
Significant Difference ◽  
One Year ◽  
Liver Tests

Abstract Background The natural history of primary sclerosing cholangitis (PSC) in children seems to differ from PSC in adults. However, studies on this matter have been limited by short follow-up periods and inconsistent classification of patients with autoimmune cholangitis (AIC) (or overlap syndrome). Consequently, it remains unclear if long-term outcomes are affected by the clinical phenotype. Aims The aims of this is study are to describe the long-term evolution of PSC and AIC in a pediatric cohort with extension of follow-up into adulthood and to evaluate the influence of phenotype on clinical outcomes. Methods This is a retrospective study of patients with AIC or PSC followed at CHU-Sainte-Justine, a pediatric referral center in Montreal. All charts between January 1998 and December 2019 were reviewed. Patients were classified as either AIC (duct disease on cholangiography with histological features of autoimmune hepatitis) or PSC (large or small duct disease on cholangiography and/or histology). Extension of follow-up after the age of 18 was done for patients followed at the Centre hospitalier de l’Université de Montréal. Clinical features at diagnosis, response to treatment at one year and liver-related outcomes were compared. Results 40 patients (27 PSC and 13 AIC) were followed for a median time of 71 months (range 2 to 347), with 52.5% followed into adulthood. 70% (28/40) had associated inflammatory bowel disease (IBD) (78% PSC vs 54% AIC; p=0.15). A similar proportion of patients had biopsy-proven significant fibrosis at diagnosis (45% PSC vs 67% AIC; p=0.23). Baseline liver tests were similar in both groups. At diagnosis, all patients were treated with ursodeoxycholic acid. Significantly more patients with AIC (77% AIC vs 30 % PSC; p=0.005) were initially treated with immunosuppressive drugs, without a significant difference in the use of Anti-TNF agents (0% AIC vs 15% PSC; p= 0.12). At one year, 55% (15/27) of patients in the PSC group had normal liver tests versus only 15% (2/13) in the AIC group (p=0.02). During follow-up, more liver-related events (cholangitis, liver transplant and cirrhosis) were reported in the AIC group (HR=3.7 (95% CI: 1.4–10), p=0.01). Abnormal liver tests at one year were a strong predictor of liver-related events during follow-up (HR=8.9(95% CI: 1.2–67.4), p=0.03), while having IBD was not (HR=0.48 (95% CI: 0.15–1.5), p=0.22). 5 patients required liver transplantation with no difference between both groups (8% CAI vs 15% CSP; p=0.53). Conclusions Pediatric patients with AIC and PSC show, at onset, similar stage of liver disease with comparable clinical and biochemical characteristics. However, patients with AIC receive more often immunosuppressive therapy and treatment response is less frequent. AIC is associated with more liver-related events and abnormal liver tests at one year are predictor of bad outcomes. Funding Agencies None

scholarly journals “The Looming, Crazy Stalker Coronavirus”: Fear Mongering, Fake News, and the Diffusion of Distrust

2021 ◽  
Vol 7 ◽  
pp. 237802312110247
Author(s):  
Alexandrea J. Ravenelle ◽  
Abigail Newell ◽  
Ken Cai Kowalski
Keyword(s):  
Mental Health ◽  
Media Coverage ◽  
Media Consumption ◽  
Fake News ◽  
Compensatory Control ◽  
The Media ◽  
Good For ◽  
Fear Mongering ◽  
One Year

The authors explore media distrust among a sample of precarious and gig workers interviewed during the COVID-19 pandemic. Although these left-leaning respondents initially increased their media consumption at the outset of the pandemic, they soon complained of media sensationalism and repurposed a readily available cultural tool: claims of “fake news.” As a result, these unsettled times have resulted in a “diffusion of distrust,” in which an elite conservative discourse of skepticism toward the media has also become a popular form of compensatory control among self-identified liberals. Perceiving “fake news” and media sensationalism as “not good” for their mental health, respondents also reported experiencing media burnout and withdrawing from media consumption. As the pandemic passes its one-year anniversary, this research has implications for long-term media coverage on COVID-19 and ongoing media trust and consumption.

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