Articles | Volume 5, issue 1
https://doi.org/10.5194/gi-5-17-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/gi-5-17-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
05 Feb 2016
Research article |
| 05 Feb 2016
Removing low-frequency artefacts from Datawell DWR-G4 wave buoy measurements
J.-V. Björkqvist
CORRESPONDING AUTHOR
Finnish Meteorological Institute, Helsinki, Finland
H. Pettersson
Finnish Meteorological Institute, Helsinki, Finland
L. Laakso
Finnish Meteorological Institute, Helsinki, Finland
Unit for Environmental Sciences and Management, North-West University, Potchefstroom, Republic of South Africa
K. K. Kahma
Finnish Meteorological Institute, Helsinki, Finland
H. Jokinen
Finnish Meteorological Institute, Helsinki, Finland
P. Kosloff
Finnish Meteorological Institute, Helsinki, Finland
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Martti Honkanen, Juha-Pekka Tuovinen, Tuomas Laurila, Timo Mäkelä, Juha Hatakka, Sami Kielosto, and Lauri Laakso
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Andrew D. Venter, Pieter G. van Zyl, Johan P. Beukes, Micky Josipovic, Johan Hendriks, Ville Vakkari, and Lauri Laakso
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This study presents measurements of carbon dioxide exchange between the atmosphere and a grazed savanna grassland ecosystem for 3 years. We find that the yearly variation in carbon dioxide balance is largely determined by the changes in the early wet season balance (September to November) and in the mid-growing season balance (December to January).
Kerneels Jaars, Pieter G. van Zyl, Johan P. Beukes, Heidi Hellén, Ville Vakkari, Micky Josipovic, Andrew D. Venter, Matti Räsänen, Leandra Knoetze, Dirk P. Cilliers, Stefan J. Siebert, Markku Kulmala, Janne Rinne, Alex Guenther, Lauri Laakso, and Hannele Hakola
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Vasco M. N. C. S. Vieira, Pavel Jurus, Emanuela Clementi, Heidi Pettersson, and Marcos Mateus
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2016-273, https://doi.org/10.5194/gmd-2016-273, 2016
Revised manuscript has not been submitted
V. M. N. C. S. Vieira, E. Sahlée, P. Jurus, E. Clementi, H. Pettersson, and M. Mateus
Biogeosciences Discuss., https://doi.org/10.5194/bgd-12-15901-2015, https://doi.org/10.5194/bgd-12-15901-2015, 2015
Manuscript not accepted for further review
V. M. N. C. S. Vieira, E. Sahlée, P. Jurus, E. Clementi, H. Pettersson, and M. Mateus
Biogeosciences Discuss., https://doi.org/10.5194/bgd-12-15925-2015, https://doi.org/10.5194/bgd-12-15925-2015, 2015
Manuscript not accepted for further review
F. Kuik, A. Lauer, J. P. Beukes, P. G. Van Zyl, M. Josipovic, V. Vakkari, L. Laakso, and G. T. Feig
Atmos. Chem. Phys., 15, 8809–8830, https://doi.org/10.5194/acp-15-8809-2015, https://doi.org/10.5194/acp-15-8809-2015, 2015
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E. Giannakaki, A. Pfüller, K. Korhonen, T. Mielonen, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, M. Josipovic, P. Tiitta, K. Chiloane, S. Piketh, H. Lihavainen, K. E. J. Lehtinen, and M. Komppula
Atmos. Chem. Phys., 15, 5429–5442, https://doi.org/10.5194/acp-15-5429-2015, https://doi.org/10.5194/acp-15-5429-2015, 2015
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In this study we summarize 1 year of Raman lidar observations over South Africa. The analyses of lidar measurements presented here could assist in bridging existing gaps in the knowledge of vertical distribution of aerosols above South Africa, since limited long-term data of this type are available for this region. For the first time, we have been able to cover the full seasonal cycle on geometrical characteristics and optical properties of free tropospheric aerosol layers in the region.
A.-M. Sundström, A. Nikandrova, K. Atlaskina, T. Nieminen, V. Vakkari, L. Laakso, J. P. Beukes, A. Arola, P. G. van Zyl, M. Josipovic, A. D. Venter, K. Jaars, J. J. Pienaar, S. Piketh, A. Wiedensohler, E. K. Chiloane, G. de Leeuw, and M. Kulmala
Atmos. Chem. Phys., 15, 4983–4996, https://doi.org/10.5194/acp-15-4983-2015, https://doi.org/10.5194/acp-15-4983-2015, 2015
J. Backman, A. Virkkula, V. Vakkari, J. P. Beukes, P. G. Van Zyl, M. Josipovic, S. Piketh, P. Tiitta, K. Chiloane, T. Petäjä, M. Kulmala, and L. Laakso
Atmos. Meas. Tech., 7, 4285–4298, https://doi.org/10.5194/amt-7-4285-2014, https://doi.org/10.5194/amt-7-4285-2014, 2014
K. Jaars, J. P. Beukes, P. G. van Zyl, A. D. Venter, M. Josipovic, J. J. Pienaar, V. Vakkari, H. Aaltonen, H. Laakso, M. Kulmala, P. Tiitta, A. Guenther, H. Hellén, L. Laakso, and H. Hakola
Atmos. Chem. Phys., 14, 7075–7089, https://doi.org/10.5194/acp-14-7075-2014, https://doi.org/10.5194/acp-14-7075-2014, 2014
K. Korhonen, E. Giannakaki, T. Mielonen, A. Pfüller, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, A. Ramandh, L. Ntsangwane, M. Josipovic, P. Tiitta, G. Fourie, I. Ngwana, K. Chiloane, and M. Komppula
Atmos. Chem. Phys., 14, 4263–4278, https://doi.org/10.5194/acp-14-4263-2014, https://doi.org/10.5194/acp-14-4263-2014, 2014
P. Tiitta, V. Vakkari, P. Croteau, J. P. Beukes, P. G. van Zyl, M. Josipovic, A. D. Venter, K. Jaars, J. J. Pienaar, N. L. Ng, M. R. Canagaratna, J. T. Jayne, V.-M. Kerminen, H. Kokkola, M. Kulmala, A. Laaksonen, D. R. Worsnop, and L. Laakso
Atmos. Chem. Phys., 14, 1909–1927, https://doi.org/10.5194/acp-14-1909-2014, https://doi.org/10.5194/acp-14-1909-2014, 2014
A. I. Partanen, A. Laakso, A. Schmidt, H. Kokkola, T. Kuokkanen, J.-P. Pietikäinen, V.-M. Kerminen, K. E. J. Lehtinen, L. Laakso, and H. Korhonen
Atmos. Chem. Phys., 13, 12059–12071, https://doi.org/10.5194/acp-13-12059-2013, https://doi.org/10.5194/acp-13-12059-2013, 2013
A. Hirsikko, V. Vakkari, P. Tiitta, J. Hatakka, V.-M. Kerminen, A.-M. Sundström, J. P. Beukes, H. E. Manninen, M. Kulmala, and L. Laakso
Atmos. Chem. Phys., 13, 5523–5532, https://doi.org/10.5194/acp-13-5523-2013, https://doi.org/10.5194/acp-13-5523-2013, 2013
V. Vakkari, J. P. Beukes, H. Laakso, D. Mabaso, J. J. Pienaar, M. Kulmala, and L. Laakso
Atmos. Chem. Phys., 13, 1751–1770, https://doi.org/10.5194/acp-13-1751-2013, https://doi.org/10.5194/acp-13-1751-2013, 2013
L. Riuttanen, M. Dal Maso, G. de Leeuw, I. Riipinen, L. Sogacheva, V. Vakkari, L. Laakso, and M. Kulmala
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-4289-2013, https://doi.org/10.5194/acpd-13-4289-2013, 2013
Revised manuscript has not been submitted
J. Leppä, S. Gagné, L. Laakso, H. E. Manninen, K. E. J. Lehtinen, M. Kulmala, and V.-M. Kerminen
Atmos. Chem. Phys., 13, 463–486, https://doi.org/10.5194/acp-13-463-2013, https://doi.org/10.5194/acp-13-463-2013, 2013
A.-P. Hyvärinen, V. Vakkari, L. Laakso, R. K. Hooda, V. P. Sharma, T. S. Panwar, J. P. Beukes, P. G. van Zyl, M. Josipovic, R. M. Garland, M. O. Andreae, U. Pöschl, and A. Petzold
Atmos. Meas. Tech., 6, 81–90, https://doi.org/10.5194/amt-6-81-2013, https://doi.org/10.5194/amt-6-81-2013, 2013
V.-M. Kerminen, M. Paramonov, T. Anttila, I. Riipinen, C. Fountoukis, H. Korhonen, E. Asmi, L. Laakso, H. Lihavainen, E. Swietlicki, B. Svenningsson, A. Asmi, S. N. Pandis, M. Kulmala, and T. Petäjä
Atmos. Chem. Phys., 12, 12037–12059, https://doi.org/10.5194/acp-12-12037-2012, https://doi.org/10.5194/acp-12-12037-2012, 2012
Related subject area
Ocean instruments
Glider observations of thermohaline staircases in the tropical North Atlantic using an automated classifier
Continuous in situ measurement of dissolved methane in Lake Kivu using a membrane inlet laser spectrometer
A comprehensive data quality evaluation method for the currents of marine controlled-source electromagnetic transmitters based on the analytic hierarchy process
Evaluations of an ocean bottom electro-magnetometer and preliminary results offshore NE Taiwan
Simple, affordable, and sustainable borehole observatories for complex monitoring objectives
Drilling cores on the sea floor with the remote-controlled sea floor drilling rig MeBo
Callum Rollo, Karen J. Heywood, and Rob A. Hall
Geosci. Instrum. Method. Data Syst., 11, 359–373, https://doi.org/10.5194/gi-11-359-2022, https://doi.org/10.5194/gi-11-359-2022, 2022
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Using an underwater buoyancy-powered autonomous glider, we collected profiles of temperature and salinity from the ocean north-east of Barbados. Most of the temperature and salinity profiles contained staircase-like structures of alternating constant values and large gradients. We wrote an algorithm to identify these staircases. We hypothesise that these staircases are prevented from forming where background gradients in temperature and salinity are too great.
Roberto Grilli, François Darchambeau, Jérôme Chappellaz, Ange Mugisha, Jack Triest, and Augusta Umutoni
Geosci. Instrum. Method. Data Syst., 9, 141–151, https://doi.org/10.5194/gi-9-141-2020, https://doi.org/10.5194/gi-9-141-2020, 2020
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We report the results from the deployment of a newly developed in situ sensor for dissolved gas measurements. Its adaptation to high gas concentrations and dissolved gas pressures was proven. The campaign leads to a first continuous profile of methane on the first 150 m and allowed us to compare the data with previous measurements. The fast response of the instrument makes this technique a good candidate for regular monitoring of those type of lakes, for anticipating disastrous gas eruptions.
Rui Yang, Meng Wang, Gongxiang Wang, Ming Deng, Jianen Jing, and Xiancheng Li
Geosci. Instrum. Method. Data Syst., 9, 69–77, https://doi.org/10.5194/gi-9-69-2020, https://doi.org/10.5194/gi-9-69-2020, 2020
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An electromagnetic transmitter sends an electromagnetic wave to the seabed; the receiver located on the seafloor receives the electromagnetic wave which carries the information of the geosphere.
In this paper, an algorithm is proposed to improve the current quality of marine electromagnetic transmitters. It has an anomaly detection function for the unstable part of the transmitting current. Our results show that the instability of transmitting-current data can cause obvious anomalies.
Ching-Ren Lin, Chih-Wen Chiang, Kuei-Yi Huang, Yu-Hung Hsiao, Po-Chi Chen, Hsu-Kuang Chang, Jia-Pu Jang, Kun-Hui Chang, Feng-Sheng Lin, Saulwood Lin, and Ban-Yuan Kuo
Geosci. Instrum. Method. Data Syst., 8, 265–276, https://doi.org/10.5194/gi-8-265-2019, https://doi.org/10.5194/gi-8-265-2019, 2019
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The first stage of field experiments involving the design and construction of a low power-consumption ocean bottom electro-magnetometer (OBEM) has been completed: this can be deployed more than 180 d on the seafloor with a time drift of less than 0.95 ppm. We found that the inclinations and magnetic data of the OBEM varied with two observed earthquakes when compared to the OBS data. The potential fields of the OBEM were slightly, but not obviously, affected by the earthquakes.
A. Kopf, T. Freudenthal, V. Ratmeyer, M. Bergenthal, M. Lange, T. Fleischmann, S. Hammerschmidt, C. Seiter, and G. Wefer
Geosci. Instrum. Method. Data Syst., 4, 99–109, https://doi.org/10.5194/gi-4-99-2015, https://doi.org/10.5194/gi-4-99-2015, 2015
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Seafloor drill rigs are remotely operated systems that provide a cost-effective means to recover sedimentary records of the upper sub-seafloor deposits. Recent increases in their payload included downhole logging tools or autoclave coring systems. Here we report on another milestone in using seafloor rigs: the development and installation of shallow borehole observatories for the MARUM-MeBo seafloor drill developed at University of Bremen, Germany.
T. Freudenthal and G. Wefer
Geosci. Instrum. Method. Data Syst., 2, 329–337, https://doi.org/10.5194/gi-2-329-2013, https://doi.org/10.5194/gi-2-329-2013, 2013
Cited articles
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Short summary
We identified a previously unknown artefact in the Datawell DWR-G4 wave buoy, which measures the GPS signal to resolve surface water waves. The artefact interferes with the part of the measurements containing information about the longer waves and must be removed to obtain accurate readings. We presented a correction method and found it to be accurate based on a comparison to measurements from a larger wave buoy that measures the movements of the device without using the GPS signal.
We identified a previously unknown artefact in the Datawell DWR-G4 wave buoy, which measures the...
