Origin and evolutionary history of Populus (Salicaceae): Further insights based on time divergence and biogeographic analysis by Xia Liu, Xia Liu, Zhaoshan Wang, Wei Wang, Qinqin Huang, Qinqin Huang, Yanfei Zeng, Yu Jin, Honglei Li, Shuhui Du, Jianguo Zhang

“…IntroductionPopulus (Salicaceae) species harbour rich biodiversity and are widely distributed throughout the Northern Hemisphere. However, the origin and biogeography of Populus remain poorly understood.MethodsWe infer the divergence times and the historical biogeography of the genus Populus through phylogenetic analysis of 34 chloroplast fragments based on a large sample.Results and DiscussionEurasia is the likely location of the early divergences of Salicaceae after the Cretaceous-Paleogene (K-Pg) mass extinction, followed by recurrent spread to the remainder of the Old World and the New World beginning in the Eocene; the extant Populus species began to diversity during the early Oligocene (approximately 27.24 Ma), climate changes during the Oligocene may have facilitated the diversification of modern poplar species; three separate lineages of Populus from Eurasia colonized North America in the Cenozoic via the Bering Land Bridges (BLB); We hypothesize that the present day disjunction in Populus can be explained by two scenarios: (i) Populus likely originated in Eurasia and subsequently colonized other regions, including North America; and (ii) the fact that the ancestor of the genus Populus that was once widely distributed in the Northern Hemisphere and eventually wiped out due to the higher extinction rates in North America, similar to the African Rand flora. …”
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A novel method for detecting lake ice cover using optical satellite data by Kirsikka Heinilä, Olli-Pekka Mattila, Sari Metsämäki, Sakari Väkevä, Kari Luojus, Gabriele Schwaizer, Sampsa Koponen

“…This novel method is applied in the provision of the Sentinel-3 Sea and Land Surface Temperature Radiometer (SLSTR) -based 0.005° Lake Ice Extent product (LIE-NH) for the Northern Hemisphere under the Global Land Service, a component of the Copernicus Land Service.The 0.005° resolution LIE products based on ICEmod applied to SLSTR (an extensive subset corresponding to LIE-NH) were validated against high-resolution Sentinel-2 Multispectral Instrument -images covering lakes in the different parts of the Northern Hemisphere, most of them representing both open water and ice pixels. …”
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A new model of the global biogeochemical cycle of carbonyl sulfide – Part 2: Use of carbonyl sulfide to constrain gross primary productivity in current vegetation models by T. Launois, P. Peylin, S. Belviso, B. Poulter

“…<br><br> The amplitude of variations in atmospheric OCS mixing ratios is mainly dictated by the vegetation sink over the Northern Hemisphere. This allows for bias recognition in the GPP representations of the three selected models. …”
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Ice core evidence for decoupling between midlatitude atmospheric water cycle and Greenland temperature during the last deglaciation by A. Landais, E. Capron, E. Capron, V. Masson-Delmotte, S. Toucanne, R. Rhodes, T. Popp, B. Vinther, B. Minster, F. Prié

“…In addition to the long-term global temperature increase, the last deglaciation onset is punctuated by a sequence of abrupt changes in the Northern Hemisphere. Such interplay between orbital- and millennial-scale variability is widely documented in paleoclimatic records but the underlying mechanisms are not fully understood. …”
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The Influence of Validation Colocation on <i>X</i>_<i>CO</i>₂ Satellite–Terrestrial Joint Observations by Ruoxi Li, Xiang Zhou, Tianhai Cheng, Zui Tao, Xingfa Gu, Ning Wang, Hongming Zhang, Tingting Lv

“…Moreover, an evident correlation exists between the bias and their corresponding latitudes, with a 0.20 ppm increase in bias observed for every 10<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>°</mo></mrow></semantics></math></inline-formula> increment in latitudes in the Northern Hemisphere. The bias of TCCON and OCO-2 shows a pronounced seasonal regularity, with the highest in summer. …”
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Combining short-term manipulative experiments with long-term palaeoecological investigations at high resolution to assess the response of Sphagnum peatlands to drought, fire and wa... by M. Lamentowicz, S. Słowińska, M. Słowiński, V.E.J. Jassey, B.H. Chojnicki, M.K. Reczuga, M. Zielińska, K. Marcisz, Ł. Lamentowicz, J. Barabach, M. Samson, P. Kołaczek, A. Buttler

“…Northern hemisphere peatlands are substantial carbon stores. …”
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Sixty years of radiocarbon dioxide measurements at Wellington, New Zealand: 1954–2014 by J. C. Turnbull, J. C. Turnbull, S. E. Mikaloff Fletcher, I. Ansell, G. W. Brailsford, R. C. Moss, M. W. Norris, K. Steinkamp

“…In contrast, similar clean-air sites in the Northern Hemisphere show a higher and earlier bomb ¹⁴C peak, consistent with a 1.4-year interhemispheric exchange time. …”
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Evaluation of Version 3 Total and Tropospheric Ozone Columns From Earth Polychromatic Imaging Camera on Deep Space Climate Observatory for Studying Regional Scale Ozone Variations by Natalya A. Kramarova, Jerald R. Ziemke, Liang-Kang Huang, Jay R. Herman, Krzysztof Wargan, Krzysztof Wargan, Colin J. Seftor, Gordon J. Labow, Luke D. Oman

“…Discrete wavelength radiance measurements from the Deep Space Climate Observatory (DSCOVR) Earth Polychromatic Imaging Camera (EPIC) allows derivation of global synoptic maps of total and tropospheric ozone columns every hour during Northern Hemisphere (NH) Summer or 2 hours during Northern Hemisphere winter. …”
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The diversity and biogeography of the communities of Actinobacteria in the forelands of glaciers at a continental scale by Binglin Zhang, Xiukun Wu, Gaosen Zhang, Shuyan Li, Wei Zhang, Ximing Chen, Likun Sun, Baogui Zhang, Guangxiu Liu, Tuo Chen

“…Compared with 7 other actinobacterial communities found in the forelands of glaciers globally, those in the Southern Hemisphere were significantly different from those in the Northern Hemisphere. Moreover, the communities were significantly different on the separate continents of the Northern Hemisphere. …”
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Variations in precipitation and temperature in Xinjiang (Northwest China) and their connection to atmospheric circulation by Guixiang Zhou, Guixiang Zhou, Guixiang Zhou, Yaning Chen, Junqiang Yao, Junqiang Yao, Junqiang Yao, Junqiang Yao

“…The subtropical high, Northern-Hemisphere polar vortex activities and the Tibetan Plateau have a significant impact on climate change in XJ. …”
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Constraining remote oxidation capacity with ATom observations

“…The underestimate in both model acetaldehyde and PAA is present throughout the year in both hemispheres and peaks during Northern Hemisphere summer. The addition of ocean sources of VOCs in the model increases cOHRmod by 3 % to 9 % and improves model-measurement agreement for acetaldehyde, particularly in winter, but cannot resolve the model summertime bias. …”
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Birch pollen—The unpleasant herald of spring by Marianne Raith, Ines Swoboda

“…Type I respiratory allergies to birch pollen and pollen from related trees of the order Fagales are increasing in industrialized countries, especially in the temperate zone of the Northern hemisphere, but the reasons for this increase are still debated and seem to be multifaceted. …”
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Anthropisation et maladies à tique : l’exemple de la borréliose de Lyme by Boulanger, Nathalie

“…The reasons are multifactorial but all associated with human practices, including climate change and socio-economic and eco systemic changes. In the northern hemisphere, Lyme borreliosis and its vector, the tick belonging to the Ixodes ricinus complex, are particularly studied. …”
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Hypothetical cosmogonic conception of the world order in the Tagar culture by Polyakova, O.O.

“…The plot is the same and it was suggested by the circumpolar pattern of the northern stellar sky, similar for all the inhabitants of the northern hemisphere of the Earth at the same Age. The petroglyphs of Chetvyorty Sunduk prove ancient people's knowledge of such phenomena as the precession, the motion of the celestial pole among stars and the location of the pole of the ecliptic near "Draco's head".…”
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The where and when of wetter and drier: disappearing Arctic sea ice plays a role by J A Francis

“…Adding to the growing body of evidence linking rapid Arctic warming to changing weather patterns in the northern hemisphere mid-latitudes, he concludes that sea-ice loss and associated surface warming lead to large-scale circulation patterns that favor wet summers in northern Europe and dry summers along the northern Mediterranean.…”
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Version 2.0 - pyFIRI — A free and open source Python software package of the non-auroral Earth’s lower ionosphere by Oleg Zolotov, Yulia Romanovskaya, Maria Knyazeva

“…Klaus Torkar, and Christoph Pock and provided electron density reference profiles for the Northern hemisphere and a regular 365-days year. Our extrapolated version allows electron density calculations for a leap year (days of a year – DOY – in the range [1..366]) and for both Northern and Southern hemispheres (latitude in the range [−60..60], degrees).…”
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Tularemia in Children, Turkey, September 2009–November 2012 by Hasan Tezer, Aslınur Ozkaya-Parlakay, Hakan Aykan, Mustafa Erkocoglu, Belgin Gülhan, Ahmet Demir, Saliha Kanik-Yuksek, Anil Tapisiz, Meltem Polat, Soner Kara, Ilker Devrim, Selcuk Kilic

“…Tularemia, a zoonotic disease caused by Francisella tularensis, is found throughout most of the Northern Hemisphere. It is not well known and is often misdiagnosed in children. …”
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The complete mitogenome dataset of the Critically Endangered estuarine pipefish, Syngnathus watermeyeri by Arsalan Emami-Khoyi

“…The mitochondrial phylogenetic analysis showed that S. watermeyeri diverged from its widely distributed southern African sister species S. temminckii approximately 1.5 million years ago, and the ancestor of these two southern Afican pipefish species diverged from a clade of northern hemisphere pipefishes comprising S. acus, S. rostellatus, and S. typhle approximately 5.3 million years ago. …”
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AVIATION EMISSIONS AND THEIR IMPACT ON ATMOSPHERIC CHEMISTRY by Sandra Krollová

“…The largest amounts of emissions are released in the northern hemisphere. The impact of emissions of chemical compounds by aircraft engines can be seen in context of the chemical processes occurring in the natural troposphere and stratosphere. …”
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Winter refuge for freshwater fish by Chemagin Andrey A.

“…The ecological aspect of the behavioral and physiological adaptation of fish in the autumn-winter period in water bodies of the temperate and subarctic climatic zones of the Northern Hemisphere is considered. It has been established that fish in the studied areas with a decrease in water temperature form aggregations in deep, low-speed sites for the successful wintering. …”
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