scholarly journals In search of traceability: two decades of calibrated Brewer UV measurements in Sodankylä and Jokioinen

2016 ◽  
Vol 5 (2) ◽  
pp. 531-540 ◽  
Author(s):  
Anu Heikkilä ◽  
Jakke Sakari Mäkelä ◽  
Kaisa Lakkala ◽  
Outi Meinander ◽  
Jussi Kaurola ◽  
...  

Abstract. The two Brewer spectrophotometers of the Finnish Meteorological Institute at Jokioinen and Sodankylä have been operated according to the highest levels of the WMO∕GAW (World Meteorological Organization∕Global Atmosphere Watch) recommendations with rigorous quality control and quality assurance. The calibration of the instruments is based on annual recalibrations of primary standard lamps in the VTT MIKES Metrology National Standards Laboratory in Finland and an exhaustive measurement program with measurements of standard and working lamps in the on-site optical laboratories. Over the years, the maintenance of the calibration has produced data sets of approximately 2000 lamp scans for both instruments. An extensive re-examination of the lamp measurements and the response of the spectrophotometers was carried out. The primary standard lamps were found to age on an average rate of 0.3 % per burn. The responsivity at wavelength 311 nm was found to exhibit both long-term and short-term changes. The overall long-term change was declining. In addition, abrupt changes of as large as 25 % were detected. The short-term changes were found to fluctuate on time frames shorter than the interval between the measurements of the primary standard lamps. This underlines the importance of the use of more frequently measured working standard lamps.

2021 ◽  
Vol 13 (2) ◽  
pp. 164
Author(s):  
Chuyao Luo ◽  
Xutao Li ◽  
Yongliang Wen ◽  
Yunming Ye ◽  
Xiaofeng Zhang

The task of precipitation nowcasting is significant in the operational weather forecast. The radar echo map extrapolation plays a vital role in this task. Recently, deep learning techniques such as Convolutional Recurrent Neural Network (ConvRNN) models have been designed to solve the task. These models, albeit performing much better than conventional optical flow based approaches, suffer from a common problem of underestimating the high echo value parts. The drawback is fatal to precipitation nowcasting, as the parts often lead to heavy rains that may cause natural disasters. In this paper, we propose a novel interaction dual attention long short-term memory (IDA-LSTM) model to address the drawback. In the method, an interaction framework is developed for the ConvRNN unit to fully exploit the short-term context information by constructing a serial of coupled convolutions on the input and hidden states. Moreover, a dual attention mechanism on channels and positions is developed to recall the forgotten information in the long term. Comprehensive experiments have been conducted on CIKM AnalytiCup 2017 data sets, and the results show the effectiveness of the IDA-LSTM in addressing the underestimation drawback. The extrapolation performance of IDA-LSTM is superior to that of the state-of-the-art methods.


Author(s):  
Maurice Roche

This chapter argues that the ‘spectacle’ of mega-events needs to be understood particularly at the level of host cities, and at that level in both in positive and negative terms and also in short and long-terms time-frames. Negatively events can, in the short-term, create spectacles and controversies in the form of the security they need, and in the long-term can create debts and ‘white elephant’ waste. They can also be understood in more positive terms as short-term performative ‘spectacles’ which are ‘embedded’ in the long-term physical legacies they leave in their host cities. It suggests that there are two main types of mega-event urban legacy. The main type is that of ‘place-making’ buildings and facilities, exemplified by iconic ‘starchitect’ architecture or functional architecture or both. The more secondary type is that of the ‘space-making’ creation or renewal of major green parks and open public areas. The chapter shows that while both Olympic and Expos mega-events have left ‘starchitecture’ legacies, Olympics have traditionally tended to leave more of the ‘functional complex’ type of urban places, and Expos have tended to leave more of the ‘open public space’ and ‘recreational green park’ type urban spaces.


Author(s):  
Peter A. Gell ◽  
Marie-Elodie Perga ◽  
C. Max Finlayson

Freshwater systems are continuously shaped by cyclical and directional forces of change, whether they be natural or anthropogenic. Beyond gradual transitions disturbances can reset their internal dynamics generating an abrupt ecological shift. Long-term data sets of gradual or abrupt change can be accessed by exhuming the physical, chemical, and biological remains archived in the sediment layers within lakes and wetlands. Long-term monitoring programmes offer more detailed evidence, usually over shorter time frames. In combination these records attest to the response of wetlands to climate and the impact of industrialised people. Humans have modified lake ecosystems for millennia and the condition of many wetland ecosystems have changed such that they are now regarded as novel. Long-term records provide targets for wetland restoration and can identify the main drivers of degradation. Identification of the character of modern Ramsar wetlands may be enhanced by reference to records of past state.


Author(s):  
Huug van den Dool

This is first and foremost a book about short-term climate prediction. The predictions we have in mind are for weather/climate elements, mainly temperature (T) and precipitation (P), at lead times longer than two weeks, beyond the realm of detailed Numerical Weather Prediction (NWP), i.e. predictions for the next month and the next seasons out to at most a few years. call this short-term climate so as to distinguish it from long-term climate change which is not the main subject of this book. A few decades ago “short-term climate prediction” was known as “longrange weather prediction”. In order to understand short-term climate predictions, their skill and what they reveal about the atmosphere, ocean and land, several chapters are devoted to constructing prediction methods. The approach taken is mainly empirical, which means literally that it is based in experience. We will use global data sets to represent the climate and weather humanity experienced (and measured!) in the past several decades. The idea is to use these existing data sets in order to construct prediction methods. In doing so we want to acknowledge that every measurement (with error bars) is a monument about the workings of Nature. We thought about using the word “statistical” instead of “empirical” in the title of the book. These two notions overlap, obviously, but we prefer the word “empirical” because we are driven more by intuition than by a desire to apply existing or developing new statistical theory. While constructing prediction methods we want to discover to the greatest extent possible how the physical system works from observations. While not mentioned in the title, diagnostics of the physical system will thus be an important part of the book as well. We use a variety of classical tools to diagnose the geophysical system. Some of these tools have been developed further and/or old tools are applied in novel ways. We do not intend to cover all diagnostics methods, only those that relate closely to prediction. There will be an emphasis on methods used in operational prediction. It is quite difficult to gain a comprehensive idea from existing literature about methods used in operational short-term climate prediction.


2020 ◽  
Vol 11 (4) ◽  
pp. 192-197
Author(s):  
Gavin Goldsbrough ◽  
Helen Reynolds

Background: Meloxicam is an analgesic agent with anti-inflammatory properties, commonly used in veterinary practices to treat a variety of different long-term medical conditions and is also used as a short-term pain relief following particularly traumatic surgeries. Aims: An observational study was conducted to determine whether meloxicam provides adequate pain management as a post-operative analgesic for canine ovariohysterectomies. Methods: 13 canines were admitted for ovariohysterectomy. Each patient was assessed using the Glasgow composite pain scale (CMPS) prior to surgery during the admission procedure, 15 minutes post-operatively, at discharge and at their post-operative check (POC) 3–5 days after surgery. Results: Data were statistically analysed to determine the overall effectiveness of meloxicam in reducing pain following canine ovariohysterectomy. The results showed a statistically significant difference (Kruskal-Wallis test: H3 =12.98, p=0.005) in pain scores between admission, 15 minutes post operatively, discharge and 3–5 days POC. The greatest decrease in pain score was between 15 minutes post-operatively and POC (Mann-Whitney U test: W=236, n=13, 13, p=0.0014) and between discharge and POC (Mann-Whitney U test: W=227, n=13, 13, p=0.0060). Overall, this demonstrated that there was an improvement in pain suggesting meloxicam is effective between these time frames. In addition, 69.2% (n=9) of patients in the study showed a pain score of 0, indicating an absence of pain, on their final POC. Statistical analysis was also used to determine if there was any difference in pain score between the 3, 4 or 5 day POC pain score. The results show there was no significant difference (Kruskal-Wallis test: H2 =0.090, p=0.638) suggesting that meloxicam's effectiveness was similar across this range of time post surgery. Conclusion: The results from the study indicate that meloxicam is an effective post-operative analgesic for canine patients undergoing an ovariohysterectomy.


2011 ◽  
Vol 19 ◽  
pp. S167-S168
Author(s):  
W. Wirth ◽  
C.E. McCulloch ◽  
J. Lynch ◽  
M. Nevitt ◽  
C.K. Kwoh ◽  
...  

2019 ◽  
Vol 13 (5) ◽  
pp. 1513-1528 ◽  
Author(s):  
Andrew M. Cunliffe ◽  
George Tanski ◽  
Boris Radosavljevic ◽  
William F. Palmer ◽  
Torsten Sachs ◽  
...  

Abstract. Permafrost landscapes are changing around the Arctic in response to climate warming, with coastal erosion being one of the most prominent and hazardous features. Using drone platforms, satellite images, and historic aerial photographs, we observed the rapid retreat of a permafrost coastline on Qikiqtaruk – Herschel Island, Yukon Territory, in the Canadian Beaufort Sea. This coastline is adjacent to a gravel spit accommodating several culturally significant sites and is the logistical base for the Qikiqtaruk – Herschel Island Territorial Park operations. In this study we sought to (i) assess short-term coastal erosion dynamics over fine temporal resolution, (ii) evaluate short-term shoreline change in the context of long-term observations, and (iii) demonstrate the potential of low-cost lightweight unmanned aerial vehicles (“drones”) to inform coastline studies and management decisions. We resurveyed a 500 m permafrost coastal reach at high temporal frequency (seven surveys over 40 d in 2017). Intra-seasonal shoreline changes were related to meteorological and oceanographic variables to understand controls on intra-seasonal erosion patterns. To put our short-term observations into historical context, we combined our analysis of shoreline positions in 2016 and 2017 with historical observations from 1952, 1970, 2000, and 2011. In just the summer of 2017, we observed coastal retreat of 14.5 m, more than 6 times faster than the long-term average rate of 2.2±0.1 m a−1 (1952–2017). Coastline retreat rates exceeded 1.0±0.1 m d−1 over a single 4 d period. Over 40 d, we estimated removal of ca. 0.96 m3 m−1 d−1. These findings highlight the episodic nature of shoreline change and the important role of storm events, which are poorly understood along permafrost coastlines. We found drone surveys combined with image-based modelling yield fine spatial resolution and accurately geolocated observations that are highly suitable to observe intra-seasonal erosion dynamics in rapidly changing Arctic landscapes.


2006 ◽  
Vol 2 (2) ◽  
pp. 133-155 ◽  
Author(s):  
JOHN M. ANDERIES

Societies frequently generate public infrastructure and institutional arrangements in order to mediate short-term environmental fluctuations. However, the social and ecological consequences of activities dealing with short-term disturbances may increase the vulnerability of the system to infrequent events or to long-term change in patterns of short-term variability. Exploring this possibility requires the study of long-term, transformational change. The archaeological record provides many examples of long-term change, such as the Hohokam who occupied the Phoenix Basin for over a thousand years and developed a complex irrigation society. In the eleventh and fourteenth centuries, the Hohokam society experienced reductions in complexity and scale possibly associated with regional climatic events. We apply a framework designed to explore robustness in coupled social-ecological systems to the Hohokam Cultural Sequence. Based on this analysis, a stylized formal model is developed to explore the possibility that the success of the Hohokam irrigation system and associated social structure may have increased their vulnerability to rare climactic shocks.


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