1. |
- Aaron-Morrison, Arlene P., et al.
(author)
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State of the climate in 2014
- 2015
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In: Bulletin of the American Meteorological Society. - : American Meteorological Society. - 0003-0007 .- 1520-0477. ; 96
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Journal article (peer-reviewed)abstract
- Most of the dozens of essential climate variables monitored each year in this report continued to follow their long-term trends in 2014, with several setting new records. Carbon dioxide, methane, and nitrous oxide-the major greenhouse gases released into Earth's atmosphere-once again all reached record high average atmospheric concentrations for the year. Carbon dioxide increased by 1.9 ppm to reach a globally averaged value of 397.2 ppm for 2014. Altogether, 5 major and 15 minor greenhouse gases contributed 2.94 W m-2 of direct radiative forcing, which is 36% greater than their contributions just a quarter century ago. Accompanying the record-high greenhouse gas concentrations was nominally the highest annual global surface temperature in at least 135 years of modern record keeping, according to four independent observational analyses. The warmth was distributed widely around the globe's land areas, Europe observed its warmest year on record by a large margin, with close to two dozen countries breaking their previous national temperature records; many countries in Asia had annual temperatures among their 10 warmest on record; Africa reported above-average temperatures across most of the continent throughout 2014; Australia saw its third warmest year on record, following record heat there in 2013; Mexico had its warmest year on record; and Argentina and Uruguay each had their second warmest year on record. Eastern North America was the only major region to observe a below-average annual temperature. But it was the oceans that drove the record global surface temperature in 2014. Although 2014 was largely ENSO-neutral, the globally averaged sea surface temperature (SST) was the highest on record. The warmth was particularly notable in the North Pacific Ocean where SST anomalies signaled a transition from a negative to positive phase of the Pacific decadal oscillation. In the winter of 2013/14, unusually warm water in the northeast Pacific was associated with elevated ocean heat content anomalies and elevated sea level in the region. Globally, upper ocean heat content was record high for the year, reflecting the continued increase of thermal energy in the oceans, which absorb over 90% of Earth's excess heat from greenhouse gas forcing. Owing to both ocean warming and land ice melt contributions, global mean sea level in 2014 was also record high and 67 mm greater than the 1993 annual mean, when satellite altimetry measurements began. Sea surface salinity trends over the past decade indicate that salty regions grew saltier while fresh regions became fresher, suggestive of an increased hydrological cycle over the ocean expected with global warming. As in previous years, these patterns are reflected in 2014 subsurface salinity anomalies as well. With a now decade-long trans-basin instrument array along 26°N, the Atlantic meridional overturning circulation shows a decrease in transport of-4.2 ± 2.5 Sv decade-1. Precipitation was quite variable across the globe. On balance, precipitation over the world's oceans was above average, while below average across land surfaces. Drought continued in southeastern Brazil and the western United States. Heavy rain during April-June led to devastating floods in Canada's Eastern Prairies. Above-normal summer monsoon rainfall was observed over the southern coast of West Africa, while drier conditions prevailed over the eastern Sahel. Generally, summer monsoon rainfall over eastern Africa was above normal, except in parts of western South Sudan and Ethiopia. The south Asian summer monsoon in India was below normal, with June record dry. Across the major tropical cyclone basins, 91 named storms were observed during 2014, above the 1981-2010 global average of 82. The Eastern/Central Pacific and South Indian Ocean basins experienced significantly above-normal activity in 2014; all other basins were either at or below normal. The 22 named storms in the Eastern/Central Pacific was the basin's most since 1992. Similar to 2013, the North Atlantic season was quieter than most years of the last two decades with respect to the number of storms, despite the absence of El Niño conditions during both years. In higher latitudes and at higher elevations, increased warming continued to be visible in the decline of glacier mass balance, increasing permafrost temperatures, and a deeper thawing layer in seasonally frozen soil. In the Arctic, the 2014 temperature over land areas was the fourth highest in the 115-year period of record and snow melt occurred 20-30 days earlier than the 1998-2010 average. The Greenland Ice Sheet experienced extensive melting in summer 2014. The extent of melting was above the 1981-2010 average for 90% of the melt season, contributing to the second lowest average summer albedo over Greenland since observations began in 2000 and a record-low albedo across the ice sheet for August. On the North Slope of Alaska, new record high temperatures at 20-m depth were measured at four of five permafrost observatories. In September, Arctic minimum sea ice extent was the sixth lowest since satellite records began in 1979. The eight lowest sea ice extents during this period have occurred in the last eight years. Conversely, in the Antarctic, sea ice extent countered its declining trend and set several new records in 2014, including record high monthly mean sea ice extent each month from April to November. On 20 September, a record large daily Antarctic sea ice extent of 20.14 × 106 km2 occurred. The 2014 Antarctic stratospheric ozone hole was 20.9 million km2 when averaged from 7 September to 13 October, the sixth smallest on record and continuing a decrease, albeit statistically insignificant, in area since 1998.
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2. |
- Almeida, Erika, et al.
(author)
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Antipredator responses of two anurans towards native and exotic predators
- 2011
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In: Amphibia-Reptilia. - 0173-5373 .- 1568-5381. ; 32:3, s. 341-350
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Journal article (peer-reviewed)abstract
- When faced with the risk of predation, tadpoles of many amphibian species are known to modify their phenotype. In this work we studied the effect of an exotic species, the red swamp crayfish (Procambarus clarkii), on the phenotype of two species of amphibians with different reproduction habitats: the Iberian painted frog, Discoglossus galganoi, that normally reproduces in temporary water bodies and the common toad, Bufo bufo, that reproduces in permanent water bodies. The responses were compared with the ones shown in the presence of a native predator, dragonfly (Aeshnidae) larvae. Behaviour, growth and morphology of tadpoles were monitored in a factorial experiment with five treatments. Our results showed that only the permanent habitat species altered its behaviour and life-history traits in the presence of P. clarkii; however, this was mediated by chemical cues from consumed conspecifics. Antipredator responses of B. bufo towards the exotic crayfish were similar to the ones towards the native predator, while D. galganoi responded to the dragonfly larvae but not to P. clarkii. This may be the result of infrequent colonization events of temporary habitats by the crayfish. Therefore, the consequences of the introduction of P. clarkii might be more serious for D. galganoi and other species living in temporary habitats. Species breeding in permanent habitats, more prone to having generalized antipredator responses, may be relatively protected against this exotic crayfish although the effectiveness of these responses still needs to be tested.
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3. |
- Arndt, D. S., et al.
(author)
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State of the Climate in 2016
- 2017
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In: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 98:8, s. S1-S280
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Journal article (peer-reviewed)abstract
- In 2016, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-continued to increase and reach new record highs. The 3.5 +/- 0.1 ppm rise in global annual mean carbon dioxide from 2015 to 2016 was the largest annual increase observed in the 58-year measurement record. The annual global average carbon dioxide concentration at Earth's surface surpassed 400 ppm (402.9 +/- 0.1 ppm) for the first time in the modern atmospheric measurement record and in ice core records dating back as far as 800000 years. One of the strongest El Nino events since at least 1950 dissipated in spring, and a weak La Nina evolved later in the year. Owing at least in part to the combination of El Nino conditions early in the year and a long-term upward trend, Earth's surface observed record warmth for a third consecutive year, albeit by a much slimmer margin than by which that record was set in 2015. Above Earth's surface, the annual lower troposphere temperature was record high according to all datasets analyzed, while the lower stratospheric temperature was record low according to most of the in situ and satellite datasets. Several countries, including Mexico and India, reported record high annual temperatures while many others observed near-record highs. A week-long heat wave at the end of April over the northern and eastern Indian peninsula, with temperatures surpassing 44 degrees C, contributed to a water crisis for 330 million people and to 300 fatalities. In the Arctic the 2016 land surface temperature was 2.0 degrees C above the 1981-2010 average, breaking the previous record of 2007, 2011, and 2015 by 0.8 degrees C, representing a 3.5 degrees C increase since the record began in 1900. The increasing temperatures have led to decreasing Arctic sea ice extent and thickness. On 24 March, the sea ice extent at the end of the growth season saw its lowest maximum in the 37-year satellite record, tying with 2015 at 7.2% below the 1981-2010 average. The September 2016 Arctic sea ice minimum extent tied with 2007 for the second lowest value on record, 33% lower than the 1981-2010 average. Arctic sea ice cover remains relatively young and thin, making it vulnerable to continued extensive melt. The mass of the Greenland Ice Sheet, which has the capacity to contribute similar to 7 m to sea level rise, reached a record low value. The onset of its surface melt was the second earliest, after 2012, in the 37-year satellite record. Sea surface temperature was record high at the global scale, surpassing the previous record of 2015 by about 0.01 degrees C. The global sea surface temperature trend for the 21st century-to-date of +0.162 degrees C decade(-1) is much higher than the longer term 1950-2016 trend of +0.100 degrees C decade(-1). Global annual mean sea level also reached a new record high, marking the sixth consecutive year of increase. Global annual ocean heat content saw a slight drop compared to the record high in 2015. Alpine glacier retreat continued around the globe, and preliminary data indicate that 2016 is the 37th consecutive year of negative annual mass balance. Across the Northern Hemisphere, snow cover for each month from February to June was among its four least extensive in the 47-year satellite record. Continuing a pattern below the surface, record high temperatures at 20-m depth were measured at all permafrost observatories on the North Slope of Alaska and at the Canadian observatory on northernmost Ellesmere Island. In the Antarctic, record low monthly surface pressures were broken at many stations, with the southern annular mode setting record high index values in March and June. Monthly high surface pressure records for August and November were set at several stations. During this period, record low daily and monthly sea ice extents were observed, with the November mean sea ice extent more than 5 standard deviations below the 1981-2010 average. These record low sea ice values contrast sharply with the record high values observed during 2012-14. Over the region, springtime Antarctic stratospheric ozone depletion was less severe relative to the 1991-2006 average, but ozone levels were still low compared to pre-1990 levels. Closer to the equator, 93 named tropical storms were observed during 2016, above the 1981-2010 average of 82, but fewer than the 101 storms recorded in 2015. Three basins-the North Atlantic, and eastern and western North Pacific-experienced above-normal activity in 2016. The Australian basin recorded its least active season since the beginning of the satellite era in 1970. Overall, four tropical cyclones reached the Saffir-Simpson category 5 intensity level. The strong El Nino at the beginning of the year that transitioned to a weak La Nina contributed to enhanced precipitation variability around the world. Wet conditions were observed throughout the year across southern South America, causing repeated heavy flooding in Argentina, Paraguay, and Uruguay. Wetter-than-usual conditions were also observed for eastern Europe and central Asia, alleviating the drought conditions of 2014 and 2015 in southern Russia. In the United States, California had its first wetter-than-average year since 2012, after being plagued by drought for several years. Even so, the area covered by drought in 2016 at the global scale was among the largest in the post-1950 record. For each month, at least 12% of land surfaces experienced severe drought conditions or worse, the longest such stretch in the record. In northeastern Brazil, drought conditions were observed for the fifth consecutive year, making this the longest drought on record in the region. Dry conditions were also observed in western Bolivia and Peru; it was Bolivia's worst drought in the past 25 years. In May, with abnormally warm and dry conditions already prevailing over western Canada for about a year, the human-induced Fort McMurray wildfire burned nearly 590000 hectares and became the costliest disaster in Canadian history, with $3 billion (U.S. dollars) in insured losses.
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4. |
- Arndt, D. S., et al.
(author)
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STATE OF THE CLIMATE IN 2017
- 2018
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In: Bulletin of The American Meteorological Society - (BAMS). - : American Meteorological Society. - 0003-0007 .- 1520-0477. ; 99:8, s. S1-S310
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Research review (peer-reviewed)
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5. |
- Blunden, Jessica, et al.
(author)
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State of the Climate in 2012
- 2013
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In: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 94:8, s. S1-S258
-
Journal article (peer-reviewed)abstract
- For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall.
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6. |
- Borg, Jonathan, et al.
(author)
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An Industry 4.0 Training Framework Addressing ‘COVID-19 Type’ Disruptions on Manufacturing
- 2021
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In: Digital Manufacturing Technology. - : Universal Wiser Publisher Pte. Ltd. - 2810-9309 .- 2810-9317.
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Journal article (peer-reviewed)abstract
- Although digitization in the manufacturing industry has been going on for some years, the recent COVID-19 pandemic helped reveal a number of bottlenecks and challenges that still need to be overcome. Joint ongoing research by a number of European Universities aimed at developing a systematic training framework on Industry 4.0 happened to be performed in the midst of the pandemic. COVID-19 meant that suddenly, internal and external workers of different educational backgrounds and in different roles had to rapidly adapt to new working procedures and environments whilst learning to use new technologies. This disruption helped this research group to generate specifications of a Higher Education Industry 4.0 Training Framework (HEI4.0) that is relevant to foster skills and competencies that make manufacturing more resilient to other possible scenarios requiring social distancing limitations. This paper outlines the details of the research performed and contributes the concept and value of establishing what is termed as the ‘flow-cognitive profile chart’ of a manufacturing organization to effectively help it in its transition towards digital manufacturing. Based on this concept, the paper passes on to prescribe a HEI4.0 Training Framework intended to guide manufacturing organizations in addressing ‘COVID-19 type’ manufacturing disruptions that can take place in other future unforeseen circumstances.
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7. |
- Francalanza, Emmanuel, et al.
(author)
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Specifications for a Digital Training Toolbox for Industry 4.0
- 2021
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In: FME TRANSACTIONS. - : Centre for Evaluation in Education and Science (CEON/CEES). - 1451-2092. ; 49:4, s. 886-893
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Journal article (peer-reviewed)abstract
- The development in the past decade of Industry 4.0 technologies has brought many new opportunities to manufacturers. The increased digitization of manufacturing operations has led to new modes of production and product development. This digitization has also increased the quantity of sensorial data which is easily available and which can be used to support real-time decision making. That said, with the opportunities come as well a number of challenges. Principally amongst these is a skills gap within the workforce. Without the required knowledge organisations will find it difficult and complex not only to employ these technologies, but also to develop the new manufacturing paradigms of tomorrow. Hence an innovative and effective training methodology is required to address this skills and knowledge gap. As part of the development of this methodology, this paper presents the finding of a study carried out to analyse the knowledge and skills gap, preferred learning methods and styles of trainers, current and past students in engineering Higher Education Institutions. This requirements analysis has led to the specifications for a Digital Training Toolbox, which can be utilised to support the implementation of Inudstry 4.0 technologies and organisational concepts.
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8. |
- Magalhaes, Solange, et al.
(author)
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Acacia Wood Fractionation Using Deep Eutectic Solvents : Extraction, Recovery, and Characterization of the Different Fractions
- 2022
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In: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 7:30, s. 26005-26014
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Journal article (peer-reviewed)abstract
- The selective extraction and recovery of different lignocellulosic molecules of interest from forestry residues is increasing every day not only to satisfy the needs of driving a society toward more sustainable approaches and materials (rethinking waste as a valuable resource) but also because lignocellulosic molecules have several applications. For this purpose, the development of new sustainable and ecologically benign extraction approaches has grown significantly. Deep eutectic solvents (DESs) appear as a promising alternative for the processing and manipulation of biomass. In the present study, a DES formed using choline chloride and levulinic acid (ChCl:LA) was studied to fractionate lignocellulosic residues of acacia wood (Acacia dealbata Link), an invasive species in Portugal. Different parameters, such as temperature and extraction time, were optimized to enhance the yield and purity of recovered cellulose and lignin fractions. DESs containing LA were found to be promising solvent systems, as the hydrogen bond donor was considered relevant in relation to lignin extraction and cellulose concentration. On the other hand, the increase in temperature and extraction time increases the amount of extracted material from biomass but affects the purity of lignin. The most promising DES system, ChCELA in a ratio of 1:3, was found to not significantly depolymerize the extracted lignin, which presented a similar molecular weight to a la-aft lignin. Additionally, the P-31 NMR results revealed that the extracted lignin has a high content of phenolic OH groups, which favor its reactivity. A mixture of ChCl:LA may be considered a fully renewable solvent, and the formed DES presents good potential to fractionate wood residues.
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9. |
- Magalhaes, Solange, et al.
(author)
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Enhancing Cellulose and Lignin Fractionation from Acacia Wood : Optimized Parameters Using a Deep Eutectic Solvent System and Solvent Recovery
- 2024
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In: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 29:15
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Journal article (peer-reviewed)abstract
- Cellulose and lignin, sourced from biomass, hold potential for innovative bioprocesses and biomaterials. However, traditional fractionation and purification methods often rely on harmful chemicals and high temperatures, making these processes both hazardous and costly. This study introduces a sustainable approach for fractionating acacia wood, focusing on both cellulose and lignin extraction using a deep eutectic solvent (DES) composed of choline chloride (ChCl) and levulinic acid (LA). A design of experiment was employed for the optimization of the most relevant fractionation parameters: time and temperature. In the case of the lignin, both parameters were found to be significant variables in the fractionation process (p-values of 0.0128 and 0.0319 for time and temperature, respectively), with a positive influence. Likewise, in the cellulose case, time and temperature also demonstrated a positive effect, with p-values of 0.0103 and 0.028, respectively. An optimization study was finally conducted to determine the maximum fractionation yield of lignin and cellulose. The optimized conditions were found to be 15% (w/v) of the wood sample in 1:3 ChCl:LA under a treatment temperature of 160 degrees C for 8 h. The developed method was validated through repeatability and intermediate precision studies, which yielded a coefficient of variation lower than 5%. The recovery and reuse of DES were successfully evaluated, revealing remarkable fractionation yields even after five cycles. This work demonstrates the feasibility of selectively extracting lignin and cellulose from woody biomass using a sustainable solvent, thus paving the way for valorization of invasive species biomass.
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10. |
- Putnik, Goran D., et al.
(author)
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ICARUS Pedagogical Methodologies Framework, or Reference Model
- 2022
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In: Managing And Implementing The Digital Transformation, ISIEA 2022. - Cham : Springer Nature. ; , s. 286-297
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Conference paper (peer-reviewed)abstract
- The paper presents the ICARUS Pedagogical Framework, or Reference model to address development of innovative pedagogical approaches to overcome the actual effectiveness problems in development, acquisition and application of the required knowledge and skills for the concepts related to Industry 4.0. The aim of the Pedagogical Framework is minimum twofold: 1) to define and guide and applications of innovative pedagogical methods to explore and address the needs of HEI educators and learners, and 2) to provide a model of the pedagogical methodology design space for future development and adaptations. In the send part of the paper a contribution to the formalization of the model using set theory approach is presented as well.
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