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- Other research product . 2022IndonesianAuthors:Rumadanu, F. (Friko); Masri, E. (Esther); Handayani, O. (Otih);Rumadanu, F. (Friko); Masri, E. (Esther); Handayani, O. (Otih);Publisher: Universitas Bhayangkara Jakarta RayaCountry: Indonesia
Notaris saat ini diperbolehkan melakukan sertifikasi dokumen elektronik. Kewenangan ini termaktub dalam Pasal 15 ayat (3) Undang-Undang Nomor 2 Tahun 2014 Tentang Jabatan Notaris. Selain mengesahkan akta, notaris juga dapat menyimpan berkas dalam bentuk file. Namun, tidak sedikit notaris yang masih enggan menggunakan teknologi untuk membuat dan mengesahkan sebuah akta dikarenakan adanya pertentangan antar pasal baik dalam Undang-Undang Jabatan Notaris sendiri maupun dengan pasal dalam Undang-Undang lainnya. Penelitian ini bertujuan untuk mengetahui apakah akta yang menggunakan teknologi informatika memiliki kekuatan pembuktian layaknya akta autentik dan apakah sertifikasi elektronik yang dilakukan oleh notaris sejalan dengan tugas dan jabatan notaris. Metode penelitian yang digunakan yaitu jenis penelitian hukum normatif yang dilakukan dengan cara penelaahan bahan pustaka atau data sekunder dengan menggunakan pendekatan undang-undang dan pendekatan konseptual. Penelitian ini berfokus pada akta hasil Rapat Umum Pemegang Saham Luar Biasa PT. Lippo Karawaci. Tbk yang dilakukan melalui video konferensi pada tanggal 13 Oktober 2021. Adanya ketidaksepakatan dari beberapa pemegang saham atas sertifikasi yang dilakukan secara elektronik karena dinilai dapat membuat akta tersebut menjadi akta di bawah tangan. Selain adanya pertentangan antara pasal, hal ini juga disebabkan tidak adanya peraturan pelaksana terkait pembuatan akta melalui teknologi informasi (Cyber Notary) oleh notaris sehingga perlunya pengkajian ulang terhadap Undang-Undang terkait dan pembuatan peraturan pelaksana khusus cyber notary.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . 2019Open Access EnglishAuthors:Fletcher, Tamara L.; Warden, Lisa; Sinninghe Damsté, Jaap S.; Brown, Kendrick J.; Rybczynski, Natalia; Gosse, John C.; Ballantyne, Ashley P.;Fletcher, Tamara L.; Warden, Lisa; Sinninghe Damsté, Jaap S.; Brown, Kendrick J.; Rybczynski, Natalia; Gosse, John C.; Ballantyne, Ashley P.;Project: NSF | Collaborative Research: A... (1418421), NWO | Perturbations of System E... (024.002.001), EC | PACEMAKER (226600), NSERC
The mid-Pliocene is a valuable time interval for investigating equilibrium climate at current atmospheric CO2 concentrations because atmospheric CO2 concentrations are thought to have been comparable to the current day and yet the climate and distribution of ecosystems were quite different. One intriguing, but not fully understood, feature of the early to mid-Pliocene climate is the amplified Arctic temperature response and its impact on Arctic ecosystems. Only the most recent models appear to correctly estimate the degree of warming in the Pliocene Arctic and validation of the currently proposed feedbacks is limited by scarce terrestrial records of climate and environment. Here we reconstruct the summer temperature and fire regime from a subfossil fen-peat deposit on west–central Ellesmere Island, Canada, that has been chronologically constrained using cosmogenic nuclide burial dating to 3.9+1.5/-0.5 Ma. The estimate for average mean summer temperature is 15.4±0.8 ∘C using specific bacterial membrane lipids, i.e., branched glycerol dialkyl glycerol tetraethers. This is above the proposed threshold that predicts a substantial increase in wildfire in the modern high latitudes. Macro-charcoal was present in all samples from this Pliocene section with notably higher charcoal concentration in the upper part of the sequence. This change in charcoal was synchronous with a change in vegetation that included an increase in abundance of fire-promoting Pinus and Picea. Paleo-vegetation reconstructions are consistent with warm summer temperatures, relatively low summer precipitation and an incidence of fire comparable to fire-adapted boreal forests of North America and central Siberia. To our knowledge, this site provides the northernmost evidence of fire during the Pliocene. It suggests that ecosystem productivity was greater than in the present day, providing fuel for wildfires, and that the climate was conducive to the ignition of fire during this period. The results reveal that interactions between paleo-vegetation and paleoclimate were mediated by fire in the High Arctic during the Pliocene, even though CO2 concentrations were similar to modern values.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . 2020Open Access EnglishAuthors:Pullinen, Iida; Schmitt, Sebastian; Kang, Sungah; Sarrafzadeh, Mehrnaz; Schlag, Patrick; Andres, Stefanie; Kleist, Einhard; Mentel, Thomas F.; Rohrer, Franz; Springer, Monika; +6 morePullinen, Iida; Schmitt, Sebastian; Kang, Sungah; Sarrafzadeh, Mehrnaz; Schlag, Patrick; Andres, Stefanie; Kleist, Einhard; Mentel, Thomas F.; Rohrer, Franz; Springer, Monika; Tillmann, Ralf; Wildt, Jürgen; Wu, Cheng; Zhao, Defeng; Wahner, Andreas; Kiendler-Scharr, Astrid;Project: EC | PIMMS (287382)
The formation of organic nitrates (ONs) in the gas phase and their impact on mass formation of secondary organic aerosol (SOA) was investigated in a laboratory study for α-pinene and β-pinene photooxidation. Focus was the elucidation of those mechanisms that cause the often observed suppression of SOA mass formation by NOx, and therein the role of highly oxygenated multifunctional molecules (HOMs). We observed that with increasing NOx concentration (a) the portion of HOM organic nitrates (HOM-ONs) increased, (b) the fraction of accretion products (HOM-ACCs) decreased, and (c) HOM-ACCs contained on average smaller carbon numbers. Specifically, we investigated HOM organic nitrates (HOM-ONs), arising from the termination reactions of HOM peroxy radicals with NOx, and HOM permutation products (HOM-PPs), such as ketones, alcohols, or hydroperoxides, formed by other termination reactions. Effective uptake coefficients γeff of HOMs on particles were determined. HOMs with more than six O atoms efficiently condensed on particles (γeff>0.5 on average), and for HOMs containing more than eight O atoms, every collision led to loss. There was no systematic difference in γeff for HOM-ONs and HOM-PPs arising from the same HOM peroxy radicals. This similarity is attributed to the multifunctional character of the HOMs: as functional groups in HOMs arising from the same precursor HOM peroxy radical are identical, vapor pressures should not strongly depend on the character of the final termination group. As a consequence, the suppressing effect of NOx on SOA formation cannot be simply explained by replacement of terminal functional groups by organic nitrate groups. According to their γeff all HOM-ONs with more than six O atoms will contribute to organic bound nitrate (OrgNO3) in the particulate phase. However, the fraction of OrgNO3 stored in condensable HOMs with molecular masses > 230 Da appeared to be substantially higher than the fraction of particulate OrgNO3 observed by aerosol mass spectrometry. This result suggests losses of OrgNO3 for organic nitrates in particles, probably due to hydrolysis of OrgNO3 that releases HNO3 into the gas phase but leaves behind the organic rest in the particulate phase. However, the loss of HNO3 alone could not explain the observed suppressing effect of NOx on particle mass formation from α-pinene and β-pinene. Instead we can attribute most of the reduction in SOA mass yields with increasing NOx to the significant suppression of gas phase HOM-ACCs, which have high molecular mass and are potentially important for SOA mass formation at low-NOx conditions.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . Other ORP type . 2020EnglishAuthors:Rosentreter, JA; Borges, Alberto; Raymond, PA; Deemer, BR; Holgerson, MA; Duarte, CM; Liu, S; Song, C; Allen, GH; Melack, J; +4 moreRosentreter, JA; Borges, Alberto; Raymond, PA; Deemer, BR; Holgerson, MA; Duarte, CM; Liu, S; Song, C; Allen, GH; Melack, J; Poulter, B; Olefeldt, D; Battin, TI; Eyre, BD;
handle: 2268/255063
Country: BelgiumAtmospheric methane is a potent greenhouse gas that has tripled in concentration since pre-industrial times. The causes of rising methane concentrations are poorly understood given its multiple sources and complex biogeochemistry. Natural and human-made aquatic ecosystems, including wetlands, are potentially the largest single source of methane, but their total emissions relative to other sources have not been assessed. Based on a new synthesis of inventory, remote sensing and modeling efforts, we present a bottom-up estimate of methane emissions from streams and rivers, freshwater lakes and reservoirs, estuaries, coastal wetlands (mangroves, seagrasses, salt-marshes), intertidal flats, aquaculture ponds, continental shelves, along with recently published estimates of global methane emissions from freshwater wetlands, rice paddies, the continental slope and open ocean. Our findings emphasize the high variability of aquatic methane fluxes and a possibly skewed distribution of currently available data, making global estimates sensitive to statistical assumptions. Mean emissions make aquatic ecosystems the largest source of methane globally (53% of total global methane emissions). Median emissions are 42% of the total global methane emissions. We argue that these emissions will likely increase due to urbanization, eutrophication and climate change.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product. - Other research product . 2020Open Access EnglishAuthors:Tirpitz, Jan-Lukas; Frieß, Udo; Hendrick, François; Alberti, Carlos; Allaart, Marc; Apituley, Arnoud; Bais, Alkis; Beirle, Steffen; Berkhout, Stijn; Bognar, Kristof; +55 moreTirpitz, Jan-Lukas; Frieß, Udo; Hendrick, François; Alberti, Carlos; Allaart, Marc; Apituley, Arnoud; Bais, Alkis; Beirle, Steffen; Berkhout, Stijn; Bognar, Kristof; Bösch, Tim; Bruchkouski, Ilya; Cede, Alexander; Chan, Ka Lok; Hoed, Mirjam; Donner, Sebastian; Drosoglou, Theano; Fayt, Caroline; Friedrich, Martina M.; Frumau, Arnoud; Gast, Lou; Gielen, Clio; Gomez-Martín, Laura; Hao, Nan; Hensen, Arjen; Henzing, Bas; Hermans, Christian; Jin, Junli; Kreher, Karin; Kuhn, Jonas; Lampel, Johannes; Li, Ang; Liu, Cheng; Liu, Haoran; Ma, Jianzhong; Merlaud, Alexis; Peters, Enno; Pinardi, Gaia; Piters, Ankie; Platt, Ulrich; Puentedura, Olga; Richter, Andreas; Schmitt, Stefan; Spinei, Elena; Stein Zweers, Deborah; Strong, Kimberly; Swart, Daan; Tack, Frederick; Tiefengraber, Martin; Hoff, René; Roozendael, Michel; Vlemmix, Tim; Vonk, Jan; Wagner, Thomas; Wang, Yang; Wang, Zhuoru; Wenig, Mark; Wiegner, Matthias; Wittrock, Folkard; Xie, Pinhua; Xing, Chengzhi; Xu, Jin; Yela, Margarita; Zhang, Chengxin; Zhao, Xiaoyi;Project: NSERC , EC | VERTIGO (607905), EC | QA4ECV (607405), EC | ACTRIS-2 (654109)
The second Cabauw Intercomparison of Nitrogen Dioxide measuring Instruments (CINDI-2) took place in Cabauw (the Netherlands) in September 2016 with the aim of assessing the consistency of multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of tropospheric species (NO2, HCHO, O3, HONO, CHOCHO and O4). This was achieved through the coordinated operation of 36 spectrometers operated by 24 groups from all over the world, together with a wide range of supporting reference observations (in situ analysers, balloon sondes, lidars, long-path DOAS, direct-sun DOAS, Sun photometer and meteorological instruments). In the presented study, the retrieved CINDI-2 MAX-DOAS trace gas (NO2, HCHO) and aerosol vertical profiles of 15 participating groups using different inversion algorithms are compared and validated against the colocated supporting observations, with the focus on aerosol optical thicknesses (AOTs), trace gas vertical column densities (VCDs) and trace gas surface concentrations. The algorithms are based on three different techniques: six use the optimal estimation method, two use a parameterized approach and one algorithm relies on simplified radiative transport assumptions and analytical calculations. To assess the agreement among the inversion algorithms independent of inconsistencies in the trace gas slant column density acquisition, participants applied their inversion to a common set of slant columns. Further, important settings like the retrieval grid, profiles of O3, temperature and pressure as well as aerosol optical properties and a priori assumptions (for optimal estimation algorithms) have been prescribed to reduce possible sources of discrepancies. The profiling results were found to be in good qualitative agreement: most participants obtained the same features in the retrieved vertical trace gas and aerosol distributions; however, these are sometimes at different altitudes and of different magnitudes. Under clear-sky conditions, the root-mean-square differences (RMSDs) among the results of individual participants are in the range of 0.01–0.1 for AOTs, (1.5–15) ×1014molec.cm-2 for trace gas (NO2, HCHO) VCDs and (0.3–8)×1010molec.cm-3 for trace gas surface concentrations. These values compare to approximate average optical thicknesses of 0.3, trace gas vertical columns of 90×1014molec.cm-2 and trace gas surface concentrations of 11×1010molec.cm-3 observed over the campaign period. The discrepancies originate from differences in the applied techniques, the exact implementation of the algorithms and the user-defined settings that were not prescribed. For the comparison against supporting observations, the RMSDs increase to a range of 0.02–0.2 against AOTs from the Sun photometer, (11–55)×1014molec.cm-2 against trace gas VCDs from direct-sun DOAS observations and (0.8–9)×1010molec.cm-3 against surface concentrations from the long-path DOAS instrument. This increase in RMSDs is most likely caused by uncertainties in the supporting data, spatiotemporal mismatch among the observations and simplified assumptions particularly on aerosol optical properties made for the MAX-DOAS retrieval. As a side investigation, the comparison was repeated with the participants retrieving profiles from their own differential slant column densities (dSCDs) acquired during the campaign. In this case, the consistency among the participants degrades by about 30 % for AOTs, by 180 % (40 %) for HCHO (NO2) VCDs and by 90 % (20 %) for HCHO (NO2) surface concentrations. In former publications and also during this comparison study, it was found that MAX-DOAS vertically integrated aerosol extinction coefficient profiles systematically underestimate the AOT observed by the Sun photometer. For the first time, it is quantitatively shown that for optimal estimation algorithms this can be largely explained and compensated by considering biases arising from the reduced sensitivity of MAX-DOAS observations to higher altitudes and associated a priori assumptions.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . Other ORP type . 2018EnglishAuthors:Martre, Pierre; Kimball, Bruce A.; Ottman, Michael J.; Wall, Gerard W.; White, Jeffrey W.; Asseng, Senthold; Ewert, Frank; Cammarano, Davide; Maiorano, Andrea; Aggarwal, Pramod K.; +42 moreMartre, Pierre; Kimball, Bruce A.; Ottman, Michael J.; Wall, Gerard W.; White, Jeffrey W.; Asseng, Senthold; Ewert, Frank; Cammarano, Davide; Maiorano, Andrea; Aggarwal, Pramod K.; Anothai, Jakarat; Basso, Bruno; Biernath, Christian; Challinor, Andrew J.; De Sanctis, Giacomo; Doltra, Jordi; Dumont, Benjamin; Fereres, Elias; Garcia-Vila, Margarita; Gayler, Sebastian; Hoogenboom, Gerrit; Hunt, Leslie A.; Izaurralde, Roberto C.; Jabloun, Mohamed; Jones, Curtis D.; Kassie, Belay T.; Kersebaum, Kurt C.; Koehler, Ann-Kristin; Müller, Christoph; Kumar, Soora Naresh; Liu, Bing; Lobell, David B.; Nendel, Claas; O'Leary, Garry; Olesen, Jørgen E.; Palosuo, Taru; Priesack, Eckart; Rezaei, Ehsan Eyshi; Ripoche, Dominique; Rötter, Reimund P.; Semenov, Mikhail A.; Stöckle, Claudio; Stratonovitch, Pierre; Streck, Thilo; Supit, Iwan; Tao, Fulu; Thorburn, Peter; Waha, Katharina; Wang, Enli; Wolf, Joost; Zhao, Zhigan; Zhu, Yan;
handle: 2268/234791
Country: BelgiumThe data set reported here includes the part of a Hot Serial Cereal Experiment (HSC) experiment recently used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat models and quantify their response to temperature. The HSC experiment was conducted in an open-field in a semiarid environment in the southwest USA. The data reported herewith include one hard red spring wheat cultivar (Yecora Rojo) sown approximately every six weeks from December to August for a two-year period for a total of 11 planting dates out of the 15 of the entire HSC experiment. The treatments were chosen to avoid any effect of frost on grain yields. On late fall, winter and early spring plantings temperature free-air controlled enhancement (T-FACE) apparatus utilizing infrared heaters with supplemental irrigation were used to increase air temperature by 1.3°C/2.7°C (day/night) with conditions equivalent to raising air temperature at constant relative humidity (i.e. as expected with global warming) during the whole crop growth cycle. Experimental data include local daily weather data, soil characteristics and initial conditions, detailed crop measurements taken at three growth stages during the growth cycle, and cultivar information. Simulations include both daily in-season and end-of-season results from 30 wheat models.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product. - Open AccessAuthors:Milenković, Milica R.; Papastavrou, Agyro T.; Radanović, Dušanka D.; Pevec, Andrej; Jagličić, Zvonko; Zlatar, Matija; Gruden-Pavlović, Maja; Vougioukalakis, Georgios C.; Turel, Iztok; Anđelković, Katarina K.; +1 moreMilenković, Milica R.; Papastavrou, Agyro T.; Radanović, Dušanka D.; Pevec, Andrej; Jagličić, Zvonko; Zlatar, Matija; Gruden-Pavlović, Maja; Vougioukalakis, Georgios C.; Turel, Iztok; Anđelković, Katarina K.; Čobeljić, Božidar;
handle: 21.15107/rcub_cherry_3006
Publisher: ElsevierCountry: SerbiaProject: MESTD | Interactions of natural p... (172055)Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2865] Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2858] Supplementary material for: [https://www.sciencedirect.com/science/article/pii/S0277538719301664?via%3Dihub]
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product. - Research data . 2022Open AccessAuthors:Okky Daulay; Gaojian Liu; kaixuan ye; Roel Botter; Yvan Klaver; qinggui tan; Hongxi Yu; Marcel Hoekman; Edwin Klein; Chris Roeloffzen; +2 moreOkky Daulay; Gaojian Liu; kaixuan ye; Roel Botter; Yvan Klaver; qinggui tan; Hongxi Yu; Marcel Hoekman; Edwin Klein; Chris Roeloffzen; Yang Liu; David Marpaung;Publisher: 4TU.ResearchDataCountry: NetherlandsProject: NWO | Light and sound-based sig... (15702), NWO | On-chip photonic control ... (740.018.021)
Data underlying the article: "Ultrahigh Dynamic Range and Low Noise Figure Programmable Integrated Microwave Photonic Filter". The data set consists of several different measurement results for the modulation transformer, double injection ring resonator, and microwave photonic filter responses as published in the resource article. All data is stored in files using the CSV-format. The set is structered to give the data per figure (subfigure), where each subfigure has a folder containing a README-file describing the data in that folder.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.
8 Research products, page 1 of 1
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- Other research product . 2022IndonesianAuthors:Rumadanu, F. (Friko); Masri, E. (Esther); Handayani, O. (Otih);Rumadanu, F. (Friko); Masri, E. (Esther); Handayani, O. (Otih);Publisher: Universitas Bhayangkara Jakarta RayaCountry: Indonesia
Notaris saat ini diperbolehkan melakukan sertifikasi dokumen elektronik. Kewenangan ini termaktub dalam Pasal 15 ayat (3) Undang-Undang Nomor 2 Tahun 2014 Tentang Jabatan Notaris. Selain mengesahkan akta, notaris juga dapat menyimpan berkas dalam bentuk file. Namun, tidak sedikit notaris yang masih enggan menggunakan teknologi untuk membuat dan mengesahkan sebuah akta dikarenakan adanya pertentangan antar pasal baik dalam Undang-Undang Jabatan Notaris sendiri maupun dengan pasal dalam Undang-Undang lainnya. Penelitian ini bertujuan untuk mengetahui apakah akta yang menggunakan teknologi informatika memiliki kekuatan pembuktian layaknya akta autentik dan apakah sertifikasi elektronik yang dilakukan oleh notaris sejalan dengan tugas dan jabatan notaris. Metode penelitian yang digunakan yaitu jenis penelitian hukum normatif yang dilakukan dengan cara penelaahan bahan pustaka atau data sekunder dengan menggunakan pendekatan undang-undang dan pendekatan konseptual. Penelitian ini berfokus pada akta hasil Rapat Umum Pemegang Saham Luar Biasa PT. Lippo Karawaci. Tbk yang dilakukan melalui video konferensi pada tanggal 13 Oktober 2021. Adanya ketidaksepakatan dari beberapa pemegang saham atas sertifikasi yang dilakukan secara elektronik karena dinilai dapat membuat akta tersebut menjadi akta di bawah tangan. Selain adanya pertentangan antara pasal, hal ini juga disebabkan tidak adanya peraturan pelaksana terkait pembuatan akta melalui teknologi informasi (Cyber Notary) oleh notaris sehingga perlunya pengkajian ulang terhadap Undang-Undang terkait dan pembuatan peraturan pelaksana khusus cyber notary.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . 2019Open Access EnglishAuthors:Fletcher, Tamara L.; Warden, Lisa; Sinninghe Damsté, Jaap S.; Brown, Kendrick J.; Rybczynski, Natalia; Gosse, John C.; Ballantyne, Ashley P.;Fletcher, Tamara L.; Warden, Lisa; Sinninghe Damsté, Jaap S.; Brown, Kendrick J.; Rybczynski, Natalia; Gosse, John C.; Ballantyne, Ashley P.;Project: NSF | Collaborative Research: A... (1418421), NWO | Perturbations of System E... (024.002.001), EC | PACEMAKER (226600), NSERC
The mid-Pliocene is a valuable time interval for investigating equilibrium climate at current atmospheric CO2 concentrations because atmospheric CO2 concentrations are thought to have been comparable to the current day and yet the climate and distribution of ecosystems were quite different. One intriguing, but not fully understood, feature of the early to mid-Pliocene climate is the amplified Arctic temperature response and its impact on Arctic ecosystems. Only the most recent models appear to correctly estimate the degree of warming in the Pliocene Arctic and validation of the currently proposed feedbacks is limited by scarce terrestrial records of climate and environment. Here we reconstruct the summer temperature and fire regime from a subfossil fen-peat deposit on west–central Ellesmere Island, Canada, that has been chronologically constrained using cosmogenic nuclide burial dating to 3.9+1.5/-0.5 Ma. The estimate for average mean summer temperature is 15.4±0.8 ∘C using specific bacterial membrane lipids, i.e., branched glycerol dialkyl glycerol tetraethers. This is above the proposed threshold that predicts a substantial increase in wildfire in the modern high latitudes. Macro-charcoal was present in all samples from this Pliocene section with notably higher charcoal concentration in the upper part of the sequence. This change in charcoal was synchronous with a change in vegetation that included an increase in abundance of fire-promoting Pinus and Picea. Paleo-vegetation reconstructions are consistent with warm summer temperatures, relatively low summer precipitation and an incidence of fire comparable to fire-adapted boreal forests of North America and central Siberia. To our knowledge, this site provides the northernmost evidence of fire during the Pliocene. It suggests that ecosystem productivity was greater than in the present day, providing fuel for wildfires, and that the climate was conducive to the ignition of fire during this period. The results reveal that interactions between paleo-vegetation and paleoclimate were mediated by fire in the High Arctic during the Pliocene, even though CO2 concentrations were similar to modern values.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . 2020Open Access EnglishAuthors:Pullinen, Iida; Schmitt, Sebastian; Kang, Sungah; Sarrafzadeh, Mehrnaz; Schlag, Patrick; Andres, Stefanie; Kleist, Einhard; Mentel, Thomas F.; Rohrer, Franz; Springer, Monika; +6 morePullinen, Iida; Schmitt, Sebastian; Kang, Sungah; Sarrafzadeh, Mehrnaz; Schlag, Patrick; Andres, Stefanie; Kleist, Einhard; Mentel, Thomas F.; Rohrer, Franz; Springer, Monika; Tillmann, Ralf; Wildt, Jürgen; Wu, Cheng; Zhao, Defeng; Wahner, Andreas; Kiendler-Scharr, Astrid;Project: EC | PIMMS (287382)
The formation of organic nitrates (ONs) in the gas phase and their impact on mass formation of secondary organic aerosol (SOA) was investigated in a laboratory study for α-pinene and β-pinene photooxidation. Focus was the elucidation of those mechanisms that cause the often observed suppression of SOA mass formation by NOx, and therein the role of highly oxygenated multifunctional molecules (HOMs). We observed that with increasing NOx concentration (a) the portion of HOM organic nitrates (HOM-ONs) increased, (b) the fraction of accretion products (HOM-ACCs) decreased, and (c) HOM-ACCs contained on average smaller carbon numbers. Specifically, we investigated HOM organic nitrates (HOM-ONs), arising from the termination reactions of HOM peroxy radicals with NOx, and HOM permutation products (HOM-PPs), such as ketones, alcohols, or hydroperoxides, formed by other termination reactions. Effective uptake coefficients γeff of HOMs on particles were determined. HOMs with more than six O atoms efficiently condensed on particles (γeff>0.5 on average), and for HOMs containing more than eight O atoms, every collision led to loss. There was no systematic difference in γeff for HOM-ONs and HOM-PPs arising from the same HOM peroxy radicals. This similarity is attributed to the multifunctional character of the HOMs: as functional groups in HOMs arising from the same precursor HOM peroxy radical are identical, vapor pressures should not strongly depend on the character of the final termination group. As a consequence, the suppressing effect of NOx on SOA formation cannot be simply explained by replacement of terminal functional groups by organic nitrate groups. According to their γeff all HOM-ONs with more than six O atoms will contribute to organic bound nitrate (OrgNO3) in the particulate phase. However, the fraction of OrgNO3 stored in condensable HOMs with molecular masses > 230 Da appeared to be substantially higher than the fraction of particulate OrgNO3 observed by aerosol mass spectrometry. This result suggests losses of OrgNO3 for organic nitrates in particles, probably due to hydrolysis of OrgNO3 that releases HNO3 into the gas phase but leaves behind the organic rest in the particulate phase. However, the loss of HNO3 alone could not explain the observed suppressing effect of NOx on particle mass formation from α-pinene and β-pinene. Instead we can attribute most of the reduction in SOA mass yields with increasing NOx to the significant suppression of gas phase HOM-ACCs, which have high molecular mass and are potentially important for SOA mass formation at low-NOx conditions.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . Other ORP type . 2020EnglishAuthors:Rosentreter, JA; Borges, Alberto; Raymond, PA; Deemer, BR; Holgerson, MA; Duarte, CM; Liu, S; Song, C; Allen, GH; Melack, J; +4 moreRosentreter, JA; Borges, Alberto; Raymond, PA; Deemer, BR; Holgerson, MA; Duarte, CM; Liu, S; Song, C; Allen, GH; Melack, J; Poulter, B; Olefeldt, D; Battin, TI; Eyre, BD;
handle: 2268/255063
Country: BelgiumAtmospheric methane is a potent greenhouse gas that has tripled in concentration since pre-industrial times. The causes of rising methane concentrations are poorly understood given its multiple sources and complex biogeochemistry. Natural and human-made aquatic ecosystems, including wetlands, are potentially the largest single source of methane, but their total emissions relative to other sources have not been assessed. Based on a new synthesis of inventory, remote sensing and modeling efforts, we present a bottom-up estimate of methane emissions from streams and rivers, freshwater lakes and reservoirs, estuaries, coastal wetlands (mangroves, seagrasses, salt-marshes), intertidal flats, aquaculture ponds, continental shelves, along with recently published estimates of global methane emissions from freshwater wetlands, rice paddies, the continental slope and open ocean. Our findings emphasize the high variability of aquatic methane fluxes and a possibly skewed distribution of currently available data, making global estimates sensitive to statistical assumptions. Mean emissions make aquatic ecosystems the largest source of methane globally (53% of total global methane emissions). Median emissions are 42% of the total global methane emissions. We argue that these emissions will likely increase due to urbanization, eutrophication and climate change.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product. - Other research product . 2020Open Access EnglishAuthors:Tirpitz, Jan-Lukas; Frieß, Udo; Hendrick, François; Alberti, Carlos; Allaart, Marc; Apituley, Arnoud; Bais, Alkis; Beirle, Steffen; Berkhout, Stijn; Bognar, Kristof; +55 moreTirpitz, Jan-Lukas; Frieß, Udo; Hendrick, François; Alberti, Carlos; Allaart, Marc; Apituley, Arnoud; Bais, Alkis; Beirle, Steffen; Berkhout, Stijn; Bognar, Kristof; Bösch, Tim; Bruchkouski, Ilya; Cede, Alexander; Chan, Ka Lok; Hoed, Mirjam; Donner, Sebastian; Drosoglou, Theano; Fayt, Caroline; Friedrich, Martina M.; Frumau, Arnoud; Gast, Lou; Gielen, Clio; Gomez-Martín, Laura; Hao, Nan; Hensen, Arjen; Henzing, Bas; Hermans, Christian; Jin, Junli; Kreher, Karin; Kuhn, Jonas; Lampel, Johannes; Li, Ang; Liu, Cheng; Liu, Haoran; Ma, Jianzhong; Merlaud, Alexis; Peters, Enno; Pinardi, Gaia; Piters, Ankie; Platt, Ulrich; Puentedura, Olga; Richter, Andreas; Schmitt, Stefan; Spinei, Elena; Stein Zweers, Deborah; Strong, Kimberly; Swart, Daan; Tack, Frederick; Tiefengraber, Martin; Hoff, René; Roozendael, Michel; Vlemmix, Tim; Vonk, Jan; Wagner, Thomas; Wang, Yang; Wang, Zhuoru; Wenig, Mark; Wiegner, Matthias; Wittrock, Folkard; Xie, Pinhua; Xing, Chengzhi; Xu, Jin; Yela, Margarita; Zhang, Chengxin; Zhao, Xiaoyi;Project: NSERC , EC | VERTIGO (607905), EC | QA4ECV (607405), EC | ACTRIS-2 (654109)
The second Cabauw Intercomparison of Nitrogen Dioxide measuring Instruments (CINDI-2) took place in Cabauw (the Netherlands) in September 2016 with the aim of assessing the consistency of multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of tropospheric species (NO2, HCHO, O3, HONO, CHOCHO and O4). This was achieved through the coordinated operation of 36 spectrometers operated by 24 groups from all over the world, together with a wide range of supporting reference observations (in situ analysers, balloon sondes, lidars, long-path DOAS, direct-sun DOAS, Sun photometer and meteorological instruments). In the presented study, the retrieved CINDI-2 MAX-DOAS trace gas (NO2, HCHO) and aerosol vertical profiles of 15 participating groups using different inversion algorithms are compared and validated against the colocated supporting observations, with the focus on aerosol optical thicknesses (AOTs), trace gas vertical column densities (VCDs) and trace gas surface concentrations. The algorithms are based on three different techniques: six use the optimal estimation method, two use a parameterized approach and one algorithm relies on simplified radiative transport assumptions and analytical calculations. To assess the agreement among the inversion algorithms independent of inconsistencies in the trace gas slant column density acquisition, participants applied their inversion to a common set of slant columns. Further, important settings like the retrieval grid, profiles of O3, temperature and pressure as well as aerosol optical properties and a priori assumptions (for optimal estimation algorithms) have been prescribed to reduce possible sources of discrepancies. The profiling results were found to be in good qualitative agreement: most participants obtained the same features in the retrieved vertical trace gas and aerosol distributions; however, these are sometimes at different altitudes and of different magnitudes. Under clear-sky conditions, the root-mean-square differences (RMSDs) among the results of individual participants are in the range of 0.01–0.1 for AOTs, (1.5–15) ×1014molec.cm-2 for trace gas (NO2, HCHO) VCDs and (0.3–8)×1010molec.cm-3 for trace gas surface concentrations. These values compare to approximate average optical thicknesses of 0.3, trace gas vertical columns of 90×1014molec.cm-2 and trace gas surface concentrations of 11×1010molec.cm-3 observed over the campaign period. The discrepancies originate from differences in the applied techniques, the exact implementation of the algorithms and the user-defined settings that were not prescribed. For the comparison against supporting observations, the RMSDs increase to a range of 0.02–0.2 against AOTs from the Sun photometer, (11–55)×1014molec.cm-2 against trace gas VCDs from direct-sun DOAS observations and (0.8–9)×1010molec.cm-3 against surface concentrations from the long-path DOAS instrument. This increase in RMSDs is most likely caused by uncertainties in the supporting data, spatiotemporal mismatch among the observations and simplified assumptions particularly on aerosol optical properties made for the MAX-DOAS retrieval. As a side investigation, the comparison was repeated with the participants retrieving profiles from their own differential slant column densities (dSCDs) acquired during the campaign. In this case, the consistency among the participants degrades by about 30 % for AOTs, by 180 % (40 %) for HCHO (NO2) VCDs and by 90 % (20 %) for HCHO (NO2) surface concentrations. In former publications and also during this comparison study, it was found that MAX-DOAS vertically integrated aerosol extinction coefficient profiles systematically underestimate the AOT observed by the Sun photometer. For the first time, it is quantitatively shown that for optimal estimation algorithms this can be largely explained and compensated by considering biases arising from the reduced sensitivity of MAX-DOAS observations to higher altitudes and associated a priori assumptions.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact. - Other research product . Other ORP type . 2018EnglishAuthors:Martre, Pierre; Kimball, Bruce A.; Ottman, Michael J.; Wall, Gerard W.; White, Jeffrey W.; Asseng, Senthold; Ewert, Frank; Cammarano, Davide; Maiorano, Andrea; Aggarwal, Pramod K.; +42 moreMartre, Pierre; Kimball, Bruce A.; Ottman, Michael J.; Wall, Gerard W.; White, Jeffrey W.; Asseng, Senthold; Ewert, Frank; Cammarano, Davide; Maiorano, Andrea; Aggarwal, Pramod K.; Anothai, Jakarat; Basso, Bruno; Biernath, Christian; Challinor, Andrew J.; De Sanctis, Giacomo; Doltra, Jordi; Dumont, Benjamin; Fereres, Elias; Garcia-Vila, Margarita; Gayler, Sebastian; Hoogenboom, Gerrit; Hunt, Leslie A.; Izaurralde, Roberto C.; Jabloun, Mohamed; Jones, Curtis D.; Kassie, Belay T.; Kersebaum, Kurt C.; Koehler, Ann-Kristin; Müller, Christoph; Kumar, Soora Naresh; Liu, Bing; Lobell, David B.; Nendel, Claas; O'Leary, Garry; Olesen, Jørgen E.; Palosuo, Taru; Priesack, Eckart; Rezaei, Ehsan Eyshi; Ripoche, Dominique; Rötter, Reimund P.; Semenov, Mikhail A.; Stöckle, Claudio; Stratonovitch, Pierre; Streck, Thilo; Supit, Iwan; Tao, Fulu; Thorburn, Peter; Waha, Katharina; Wang, Enli; Wolf, Joost; Zhao, Zhigan; Zhu, Yan;
handle: 2268/234791
Country: BelgiumThe data set reported here includes the part of a Hot Serial Cereal Experiment (HSC) experiment recently used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat models and quantify their response to temperature. The HSC experiment was conducted in an open-field in a semiarid environment in the southwest USA. The data reported herewith include one hard red spring wheat cultivar (Yecora Rojo) sown approximately every six weeks from December to August for a two-year period for a total of 11 planting dates out of the 15 of the entire HSC experiment. The treatments were chosen to avoid any effect of frost on grain yields. On late fall, winter and early spring plantings temperature free-air controlled enhancement (T-FACE) apparatus utilizing infrared heaters with supplemental irrigation were used to increase air temperature by 1.3°C/2.7°C (day/night) with conditions equivalent to raising air temperature at constant relative humidity (i.e. as expected with global warming) during the whole crop growth cycle. Experimental data include local daily weather data, soil characteristics and initial conditions, detailed crop measurements taken at three growth stages during the growth cycle, and cultivar information. Simulations include both daily in-season and end-of-season results from 30 wheat models.
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You have already added works in your ORCID record related to the merged Research product. - Open AccessAuthors:Milenković, Milica R.; Papastavrou, Agyro T.; Radanović, Dušanka D.; Pevec, Andrej; Jagličić, Zvonko; Zlatar, Matija; Gruden-Pavlović, Maja; Vougioukalakis, Georgios C.; Turel, Iztok; Anđelković, Katarina K.; +1 moreMilenković, Milica R.; Papastavrou, Agyro T.; Radanović, Dušanka D.; Pevec, Andrej; Jagličić, Zvonko; Zlatar, Matija; Gruden-Pavlović, Maja; Vougioukalakis, Georgios C.; Turel, Iztok; Anđelković, Katarina K.; Čobeljić, Božidar;
handle: 21.15107/rcub_cherry_3006
Publisher: ElsevierCountry: SerbiaProject: MESTD | Interactions of natural p... (172055)Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2865] Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2858] Supplementary material for: [https://www.sciencedirect.com/science/article/pii/S0277538719301664?via%3Dihub]
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product. - Research data . 2022Open AccessAuthors:Okky Daulay; Gaojian Liu; kaixuan ye; Roel Botter; Yvan Klaver; qinggui tan; Hongxi Yu; Marcel Hoekman; Edwin Klein; Chris Roeloffzen; +2 moreOkky Daulay; Gaojian Liu; kaixuan ye; Roel Botter; Yvan Klaver; qinggui tan; Hongxi Yu; Marcel Hoekman; Edwin Klein; Chris Roeloffzen; Yang Liu; David Marpaung;Publisher: 4TU.ResearchDataCountry: NetherlandsProject: NWO | Light and sound-based sig... (15702), NWO | On-chip photonic control ... (740.018.021)
Data underlying the article: "Ultrahigh Dynamic Range and Low Noise Figure Programmable Integrated Microwave Photonic Filter". The data set consists of several different measurement results for the modulation transformer, double injection ring resonator, and microwave photonic filter responses as published in the resource article. All data is stored in files using the CSV-format. The set is structered to give the data per figure (subfigure), where each subfigure has a folder containing a README-file describing the data in that folder.
Average/low popularityAverage/low popularityAverage/low influencePopularity: Citation-based measure reflecting the current impact.Average/low influenceInfluence: Citation-based measure reflecting the total impact.add Add to ORCIDPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.