scholarly journals Two distinct decadal and centennial cyclicities forced marine upwelling intensity and precipitation during the late Early Miocene in Central Europe

2014 ◽  
Vol 10 (2) ◽  
pp. 1223-1264 ◽  
Author(s):  
G. Auer ◽  
W. E. Piller ◽  
M. Harzhauser
Keyword(s):  
High Resolution ◽  
Climate Variability ◽  
Primary Productivity ◽  
Environmental Changes ◽  
Laminated Sediments ◽  
Small Scale ◽  
Short Term ◽  
Shallow Marine ◽  
North Alpine Foreland Basin ◽  
Upwelling Intensity

Abstract. Within a 5.5 m-thick succession of Upper Burdigalian (Karpatian) sediments in the North Alpine Foreland Basin (NAFB; Austria), dated to CNP-zone NN4, a high-resolution section was logged continuously. 100 samples were taken with a resolution of ~10 mm per layer and analysed using an integrated multi-proxy approach. Earlier analyses of geochemistry and calcareous nannoplankton assemblages hint at small-scale, short-term variations in palaeoenvironmental conditions, such as water-column stratification, primary productivity, organic matter flux, bottom-water oxygenation, freshwater influx and changes in relative sea-level. The results indicate a highly dynamic shallow marine setting that was subject to high frequency environmental changes on a decadal to centennial scale. Time-series analyses on nine different proxy-datasets using REDFIT-analysis and Wavelet spectra were applied to resolve a possible cyclic nature of these variations. Analyses revealed that different proxies for precipitation, upwelling intensity, and over all productivity likely were controlled by different cyclicities. A best-fit adjustment of the likely sedimentation rates within the high-resolution section resulted in periodicities fitting well with the Lower (~65 yr) and Upper (~113 yr) Gleissberg cycle as well as the Suess/de Vries cycle (~211 yr). The section covers a timespan of ~1190 yr based on the correlation with solar cycles, which resulted in an estimated sedimentation rate of 575 mm kyr−1. For the first time, short-term climate variability on a decadal to centennial scale is resolved in Lower Miocene shallow marine laminated sediments in a land-based section. The results hint at a close relationship between climate variability and solar forcing during the Late Burdigalian. Moreover, accepting that these cyclicities are indeed of solar origin, this would indicate that precipitation was driven by the two Gleissberg cycles, while upwelling was driven by the Suess cycle. Furthermore, proxies for primary productivity were influenced by both cycles, although the Suess cycle exerts dominant control, reflecting a stronger influence of upwelling on primary productivity.

scholarly journals Two distinct decadal and centennial cyclicities forced marine upwelling intensity and precipitation during the late Early Miocene in central Europe

2015 ◽  
Vol 11 (2) ◽  
pp. 283-303 ◽  
Author(s):  
G. Auer ◽  
W. E. Piller ◽  
M. Harzhauser
Keyword(s):  
High Resolution ◽  
Climate Variability ◽  
Primary Productivity ◽  
Environmental Changes ◽  
Laminated Sediments ◽  
Small Scale ◽  
Short Term ◽  
Shallow Marine ◽  
North Alpine Foreland Basin ◽  
Upwelling Intensity

Abstract. Within a 5.5 m thick succession of Upper Burdigalian (Karpatian) sediments in the North Alpine Foreland Basin (NAFB; Austria), dated to CNP-zone NN4, a high-resolution section was logged continuously. One hundred samples were taken with a resolution of ~10 mm (approximating ~17 years) per layer and analyzed using an integrated multi-proxy approach. Earlier analyses of geochemistry and calcareous nannoplankton assemblages hint at small-scale, short-term variations in paleoenvironmental conditions, such as water-column stratification, primary productivity, organic matter flux, bottom-water oxygenation, freshwater influx, and changes in relative sea level. The results indicate a highly dynamic shallow marine setting that was subject to high-frequency environmental changes on a decadal to centennial scale. Time-series analyses on nine different proxy data sets using REDFIT analysis and wavelet spectra were applied to resolve a possible cyclic nature of these variations. Analyses revealed that different proxies for precipitation, upwelling intensity, and overall productivity were likely controlled by different cyclicities. A best-fit adjustment of the likely sedimentation rates within the high-resolution section resulted in periodicities fitting well with the Lower (~65 years) and Upper (~113 years) Gleissberg cycle as well as the Suess/de Vries cycle (~211 years). The section covers a time span of ~1190 years based on the correlation with solar cycles, which resulted in an estimated sedimentation rate of 575 mm kyr−1. For the first time, short-term climate variability on a decadal to centennial scale is resolved in Lower Miocene shallow marine laminated sediments in a land-based section. The results hint at a close relationship between climate variability and solar forcing during the Late Burdigalian. Moreover, accepting that these cyclicities are indeed of solar origin, this would indicate that precipitation was driven by the two Gleissberg cycles, while upwelling was driven by the Suess cycle. Furthermore, proxies for primary productivity were influenced by both cycles, although the Suess cycle exerts dominant control, reflecting a stronger influence of upwelling on primary productivity.

scholarly journals Gloxinia—An Open-Source Sensing Platform to Monitor the Dynamic Responses of Plants

Sensors ◽  
2020 ◽  
Vol 20 (11) ◽  
pp. 3055
Author(s):  
Olivier Pieters ◽  
Tom De Swaef ◽  
Peter Lootens ◽  
Michiel Stock ◽  
Isabel Roldán-Ruiz ◽  
...  
Keyword(s):  
Open Source ◽  
Large Scale ◽  
Environmental Changes ◽  
Low Cost ◽  
Current Data ◽  
Dynamic Responses ◽  
Small Scale ◽  
Data Logging ◽  
Short Term ◽  
Sensing Platforms

The study of the dynamic responses of plants to short-term environmental changes is becoming increasingly important in basic plant science, phenotyping, breeding, crop management, and modelling. These short-term variations are crucial in plant adaptation to new environments and, consequently, in plant fitness and productivity. Scalable, versatile, accurate, and low-cost data-logging solutions are necessary to advance these fields and complement existing sensing platforms such as high-throughput phenotyping. However, current data logging and sensing platforms do not meet the requirements to monitor these responses. Therefore, a new modular data logging platform was designed, named Gloxinia. Different sensor boards are interconnected depending upon the needs, with the potential to scale to hundreds of sensors in a distributed sensor system. To demonstrate the architecture, two sensor boards were designed—one for single-ended measurements and one for lock-in amplifier based measurements, named Sylvatica and Planalta, respectively. To evaluate the performance of the system in small setups, a small-scale trial was conducted in a growth chamber. Expected plant dynamics were successfully captured, indicating proper operation of the system. Though a large scale trial was not performed, we expect the system to scale very well to larger setups. Additionally, the platform is open-source, enabling other users to easily build upon our work and perform application-specific optimisations.

2000 years of marine primary productivity in the Eastern Tropical North Pacific

2020 ◽  
Author(s):  
Christina Treinen-Crespo ◽  
Jose Carriquiry ◽  
Julio Villaescusa ◽  
Elisabet Repiso-Terrones
Keyword(s):  
High Resolution ◽  
Climate Variability ◽  
Primary Productivity ◽  
North Pacific ◽  
Biogenic Silica ◽  
Change Scenario ◽  
The Past ◽  
Past 2000 Years ◽  
Increasing Trend ◽  
Marine Primary Productivity

<p>Changes in marine primary productivity (MPP) over the 21st century are expected to occur under the prevailing climate change scenario. For better understanding of past climate variability, we reconstructed MPP at high resolution (~1-2 years) for the past 2000 years analyzing biogenic silica and total organic carbon (TOC %) on a sediment core collected from Soledad Basin (25°N, 112°W), Baja  California, Mexico. Located in the Eastern Tropical North Pacific, this suboxic basin is ideal for palaeoceanographic reconstructions due to its high sedimentation rate (2 mm/year), which allow us to reconstruct past changes in the ocean and climate at high resolution. Our results show an increasing trend in the variability of MPP for the past 2000 years: biogenic silica content does not show a well-defined trend, but rather it is dominated by strong multidecadal and prominent centennial-scale cycles while TOC (%) shows a slight increasing trend towards the present, starting at least 2000 years ago. Spectral analysis confirms the presence of multidecadal to centennial cycles. These results will be discussed in the context of the Anthropocene and natural climate variability.</p>

Holocene history of landscape development in the catchment of Lake Skogstjern, southeastern Norway, based on a high-resolution multi-proxy record

The Holocene ◽  
2017 ◽  
Vol 27 (12) ◽  
pp. 1928-1947 ◽  
Author(s):  
Magdalena Wieckowska-Lüth ◽  
Wiebke Kirleis ◽  
Walter Doerfler
Keyword(s):  
High Resolution ◽  
Environmental Changes ◽  
Animal Husbandry ◽  
Small Scale ◽  
Minor Role ◽  
Landscape Development ◽  
Proxy Record ◽  
Crop Cultivation ◽  
The Holocene ◽  
Erosion Rates

A high-resolution multi-proxy record from sediments of a small-sized lake situated in Telemark, southeastern Norway, was used to reconstruct the local landscape development of the past c. 10,500 years. Our data demonstrate that changes in vegetation composition and structure in the first two-thirds of the Holocene are principally attributable to climatic changes and high erosion rates, as deduced from geochemical and physical (loss-on-ignition) proxy analyses. The highest signals of erosional inputs to the lake (c. 8030–5760 cal. BP) can be correlated with the first part of the Holocene Thermal Maximum. Nevertheless, evidence from pollen, non-pollen palynomorphs and microscopic charcoal analyses indicates the presence of nutrient-rich and disturbed environments already during the middle Mesolithic (c. 10,050–9400 cal. BP). It also shows traces of animal husbandry (c. 5580 cal. BP) and small-scale cereal cultivation (c. 5520 cal. BP) in the early Neolithic. In subsequent periods, human impact remains at a relatively low level and does not generate significant palaeo-environmental changes. Not until the second half of the Bronze Age (c. 2840 cal. BP) is some intensification in animal husbandry recorded, whereas crop cultivation continues to play a minor role in the second millennium BP. The establishment of a full farming economy took place during the Roman Iron Age (c. 1790 cal. BP), characterised by extensive forest clearance and local fires, crop cultivation in permanent fields and the presence of open pastures. This establishment is associated with advanced soil degeneration and increased erosion rates.

scholarly journals Phenological tracking og agricultural feilds investigated by using dual polarimetry tanDEM-X images

2015 ◽  
Vol XL-7/W3 ◽  
pp. 73-76
Author(s):  
S. Mirzaee ◽  
M. Motagh ◽  
H. Arefi ◽  
A. Nooryazdan
Keyword(s):  
High Resolution ◽  
Environmental Changes ◽  
Weather Conditions ◽  
Synthetic Aperture ◽  
Small Scale ◽  
Imaging Characteristics ◽  
X Band ◽  
Phenological Changes ◽  
Extract Information

Remote sensing plays a key role in monitoring and assessing environmental changes. Because of its special imaging characteristics such as high-resolution, capabilities to obtain data in all weather conditions and sensitivity to geometrical and dielectric properties of the features, Synthetic Aperture Radar (SAR) technology has become a powerful technique to detect small scale changes related to earth surface.SAR images contain the information of both phase and intensity in different modes like single, dual and full polarimetric states which are important in order to extract information about various targets. In this study we investigate phenological changes in an agricultural region using high-resolution X-band SAR data. The case study is located in Doroud region of Lorestan province, west of Iran. The purpose is to investigate the ability of copolar and interferometric coherence extracted from TanDEM-X dual polarimetry (HH/VV) in bistatic StripMap mode for tracking the phenological changes of crops during growing season. The data include 11 images acquired between 12.06.2012 and 02.11.2012 and 6 images acquired between 30.05.2013 and 04.08.2013 in the CoSSC format. Results show that copolar coherence is almost able to follow phenological changes but interferometric coherence has a near constant behaviour with fluctuations mainly related to baseline variations.

High-resolution shallow marine seismic surveys off Busan and Pohang, Korea, using a small-scale multichannel system

2004 ◽  
Vol 56 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Ho-Young Lee ◽  
Keun-Pil Park ◽  
Nam-Hyung Koo ◽  
Dong-Geun Yoo ◽  
Dong-Hyo Kang ◽  
...  
Keyword(s):  
High Resolution ◽  
Small Scale ◽  
Multichannel System ◽  
Seismic Surveys ◽  
Shallow Marine ◽  
Marine Seismic

scholarly journals Seamless multi-model postprocessing for air temperature forecasts in complex topography

2021 ◽  
Author(s):  
Regula Keller ◽  
Jan Rajczak ◽  
Jonas Bhend ◽  
Christoph Spirig ◽  
Stephan Hemri ◽  
...  
Keyword(s):  
High Resolution ◽  
Weather Prediction ◽  
Small Scale ◽  
Model Output ◽  
Model Combination ◽  
Single Model ◽  
Short Term ◽  
Time Horizons ◽  
Direct Model ◽  
Medium Range

AbstractStatistical postprocessing is applied in operational forecasting to correct systematic errors of numerical weather prediction models (NWP) and to automatically produce calibrated local forecasts for end-users. Postprocessing is particularly relevant in complex terrain, where even state-of-the-art high-resolution NWP systems cannot resolve many of the small-scale processes shaping local weather conditions. In addition, statistical postprocessing can also be used to combine forecasts from multiple NWP systems. Here we assess an ensemble model output statistics (EMOS) approach to produce seamless temperature forecasts based on a combination of short-term ensemble forecasts from a convection-permitting limited-area ensemble and a medium-range global ensemble forecasting model. We quantify the benefit of this approach compared to only postprocessing the high-resolution NWP. The multi-model EMOS approach (’Mixed EMOS’) is able to improve forecasts by 30% with respect to direct model output from the high-resolution NWP. A detailed evaluation of Mixed EMOS reveals that it outperforms either one of the single-model EMOS versions by 8-12%. Temperature forecasts at valley locations profit in particular from the model combination. All forecast variants perform worst in winter (DJF), however calibration and model combination improves forecast quality substantially. In addition to increasing skill as compared to single model postprocessing, it also enables to seamlessly combine multiple forecast sources with different time horizons (and horizontal resolutions) and thereby consolidates short-term to medium-range forecasting time horizons in one product without any user-relevant discontinuity.

scholarly journals Correction of water column height variation on 2D grid high-resolution seismic data using dGPS based methodology

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ayobami Abegunrin ◽  
Daniel A. Hepp ◽  
Tobias Mörz
Keyword(s):  
High Resolution ◽  
Water Column ◽  
Seismic Data ◽  
Column Height ◽  
Small Scale ◽  
Seismic Profiles ◽  
Shallow Marine ◽  
Sea Floor ◽  
The North ◽  
Water Column Height

Abstract Variations in the physical properties of water column usually impede exact water column height correction on high-resolution seismic data, especially when the data are collected in shallow marine environments. Changes in water column properties can be attributed to variation in tides and currents, wind-generated swells, long and short amplitude wave-fronts, or variation in salinity and water temperature. Likewise, the proper motion of the vessel complicates the determinability of the water column height. This study provides a less time-consuming and precise differential Global Positioning System based methodology that can be applied to most types of high-resolution seismic data in order to significantly improve the tracking and quality of deduced geological interpretations on smaller depth scales. The methodology was tested on geophysical profiles obtained from the German sector of the North Sea. The focus here was to identify, distinguish and classify various sub-surface sedimentary structures in a stratigraphically highly complex shallow marine environment on decimeter small-scale. After applying the correction to the profiles, the sea floor, in general, occurs 1.1 to 3.4 m (mean of 2.2 m) deeper than the uncorrected profiles and is consistent with the sea floor from published tide corrected bathymetry data. The corrected seismic profiles were used in plotting the depth of the base of Holocene channel structures and to define their gradients. The applied correction methodology was also crucial in glacial and post-glacial valley features distinction, across profile correlation and establishing structural and stratigraphic framework of the study area.

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