The Experts below are selected from a list of 51888 Experts worldwide ranked by ideXlab platform
Patrick Roberts - One of the best experts on this subject based on the ideXlab platform.
-
tropical trees as time capsules of Anthropogenic Activity
Trends in Plant Science, 2020Co-Authors: Victor Lery Caetanoandrade, Charles R Clement, Detlef Weigel, Susan E Trumbore, Nicole Boivin, Jochen Schongart, Patrick RobertsAbstract:After the ice caps, tropical forests are globally the most threatened terrestrial environments. Modern trees are not just witnesses to growing contemporary threats but also legacies of past human Activity. Here, we review the use of dendrochronology, radiocarbon analysis, stable isotope analysis, and DNA analysis to examine ancient tree management. These methods exploit the fact that living trees record information on environmental and Anthropogenic selective forces during their own and past generations of growth, making trees living archaeological ‘sites’. The applicability of these methods across prehistoric, historic, and industrial periods means they have the potential to detect evolving Anthropogenic threats and can be used to set conservation priorities in rapidly vanishing environments.
Weining Xiang - One of the best experts on this subject based on the ideXlab platform.
-
long term trend in ground based air temperature and its responses to atmospheric circulation and Anthropogenic Activity in the yangtze river delta china
Atmospheric Research, 2017Co-Authors: Xia Peng, Qiannan She, Lingbo Long, Min Liu, Jiaxin Zhang, Weining XiangAbstract:Abstract The Yangtze River Delta (YRD), including Shanghai City, Jiangsu and Zhejiang Provinces, is the largest metropolitan region in China. In the past decades, the region has experienced massive urbanization and detrimentally affected the environment in the region. Identifying the spatio-temporal variations of climate change and its influencing mechanism in the YRD is an important task for assessing their impacts on the local society and ecosystem. Based on long-term (1958–2014) observation data of meteorological stations, three temperature indices, i.e. extreme maximum temperature (TXx), extreme minimum temperature (TNn), and mean temperature (TMm), were selected and spatialized with climatological calculations and spatial techniques. Evolution and spatial heterogeneity of three temperature indices over YRD as well as their links to atmospheric circulation and Anthropogenic Activity were investigated. In the whole YRD, a statistically significant overall uptrend could be detected in three temperature indices with the Mann-Kendall (M-K) trend test method. The linear increasing trend for TMm was 0.31 °C/10 a, which was higher than the global average (0.12 °C/10 a during 1951–2012). For TXx and TNn, the increasing rates were 0.41 °C/10 a and 0.52 °C/10 a. Partial correlation analysis indicated that TMm was more related with TXx (rp = 0.68, p
Anne M Thompson - One of the best experts on this subject based on the ideXlab platform.
-
discoveries about tropical ozone from satellite and shadoz southern hemisphere additional ozonesondes
2004Co-Authors: Anne M ThompsonAbstract:We have been producing near-real tropical tropospheric ozone ("TTO") data from TOMS since 1997 with Prof. Hudson and students at the University of Maryland. Maps for 1996-2000 for the operational Earth-Probe instrument reside at: . The tropics is a region strongly influenced by natural variability and Anthropogenic Activity and the satellite data have been used to track biomass burning pollution and to detect interannual variability and climate signals in ozone. The satellite view of chemical-dynamical interactions in tropospheric ozone is not adequate to capture vertical variability. Thus, in 1998, NASA's Goddard Space Flight Center, NOAA's Climate Monitoring and Diagnostics Laboratory (CMDL) and a team of international sponsors established the SHADOZ (Southern Hemisphere ADditional OZonesondes) project to address the gap in tropical ozone soundings. SHADOZ provides a public archive of ozonesonde data from twelve tropical and subtropical stations at http://croc.gsfc.nasa.gov/shadoz. Highlights from the first 4-5 years of SHADOZ data (presently > 2000 sondes) will be shown.
-
shadoz southern hemisphere additional ozonesondes a tropical ozonesonde radiosonde network for the atmospheric community
2003Co-Authors: Anne M Thompson, Samuel J. Oltmans, Jacquelyn C. Witte, F J SchmidlinAbstract:A lack of sounding data has limited the accuracy of ozone satellite retrievals in the tropics and our understanding of chemical-dynamical interactions in a region strongly influenced by natural variability and Anthropogenic Activity. In 1998, NASA s Goddard Space Flight Center, NOAA's Climate Monitoring and Diagnostics Laboratory (CMDL) and a team of international sponsors established the SHADOZ (Southern Hemisphere ADditional OZonesondes) project to address the gap in tropical ozone soundings. SHADOZ augments launches at selected sites and provides a public archive of ozonesonde and radiosonde data from twelve tropical and subtropical stations at http://croc.gsfc.nasa.gov/shadoz. Instrumentation, data and a summary of the first scientific findings from SHADOZ are presented.
Nicole Boivin - One of the best experts on this subject based on the ideXlab platform.
-
tropical trees as time capsules of Anthropogenic Activity
Trends in Plant Science, 2020Co-Authors: Victor Lery Caetanoandrade, Charles R Clement, Detlef Weigel, Susan E Trumbore, Nicole Boivin, Jochen Schongart, Patrick RobertsAbstract:After the ice caps, tropical forests are globally the most threatened terrestrial environments. Modern trees are not just witnesses to growing contemporary threats but also legacies of past human Activity. Here, we review the use of dendrochronology, radiocarbon analysis, stable isotope analysis, and DNA analysis to examine ancient tree management. These methods exploit the fact that living trees record information on environmental and Anthropogenic selective forces during their own and past generations of growth, making trees living archaeological ‘sites’. The applicability of these methods across prehistoric, historic, and industrial periods means they have the potential to detect evolving Anthropogenic threats and can be used to set conservation priorities in rapidly vanishing environments.
Polona Vreca - One of the best experts on this subject based on the ideXlab platform.
-
consequences of Anthropogenic Activity for two remote alpine lakes in nw slovenia as tracked by sediment geochemistry
Journal of Paleolimnology, 2013Co-Authors: Gregor Muri, Branko Cermelj, Radojko Jacimovic, Dragomir Skaberne, Andrej Smuc, Martina Burnik Sturm, Janja Tursic, Polona VrecaAbstract:Several geological and geochemical parameters were determined in the sediments of the 5th (5 J) and 6th (6 J) Triglav Lakes, Julian Alps (NW Slovenia), in order to study the impact of natural catchment characteristics and Anthropogenic Activity. Fish were introduced into both lakes in 1991 and a mountain hut lies on the shore of 5 J. Sedimentary grain size (GS) was distinctly coarser in 5 J than 6 J, with arithmetic means ranging between 46 and 60 and 23–36 μm, respectively. In contrast, the mineralogical composition of the two sediments was similar. Calcite predominated strongly, comprising more than 77 % of total minerals, while dolomite and quartz were rare. Organic carbon (OC) and total nitrogen (TN) concentrations were highest in surficial sediments, with levels of 14.4 and 1.8 %, and 19.3 and 2.4 % observed in 5 J and 6 J, respectively. C/N ratios (atomic) were lowest in the same surface sediments, with the two lakes characterized by similar values (9.6 vs. 9.4, respectively), suggesting a predominance of autochthonous organic matter (OM) in both lakes. Contemporary δ13C values were lower in 5 J (−21.0 ‰) than 6 J (−18.5 ‰) sediments. Considerable changes in these four parameters were observed in recently deposited material, reflecting a shift in the trophic status of both lakes that was likely induced by the introduction of fish. In addition, the smaller and shallower 6 J seemed to respond to changes faster than the larger and deeper 5 J, indicating the higher sensitivity of the former. δ15N values in surface sediments of 5 J and 6 J were −2.9 and −4.4 ‰, respectively, with levels increasing gradually with depth to approximately +1.0 ‰ in deeper sediments. The observed changes could most likely be attributed to the atmospheric deposition of reactive nitrogen. The mountain hut has seemingly not had a significant enough impact on the lakes to be recorded in their sediments.