| Records |
| Author |
Sean Crowell, David Baker, Andrew Schuh, Sourish Basu, Andrew R. Jacobson, Frederic Chevallier, Junjie Liu, Feng Deng, Liang Feng, Kathryn McKain, Abhishek Chatterjee, John B. Miller, Britton B. Stephens, Annmarie Eldering, David Crisp, David Schimel, Ray Nassar, Christopher W. O'Dell, Tomohiro Oda, Colm Sweeney, Paul I. Palmer, Dylan B. A. Jones |
| Title |
The 2015–2016 carbon cycle as seen from OCO-2 and the global in situ network |
Type |
Journal |
| Year |
2019 |
Publication |
Atmospheric chemistry and physics |
Abbreviated Journal |
|
| Volume |
19 |
Issue |
15 |
Pages |
9797-9831 |
| Keywords |
|
| Abstract |
The Orbiting Carbon Observatory-2 has been on orbit since 2014, and its global coverage holds the potential to reveal new information about the carbon cycle through the use of top-down atmospheric inversion methods combined with column average CO2 retrievals. We employ a large ensemble of atmospheric inversions utilizing different transport models, data assimilation techniques, and prior flux distributions in order to quantify the satellite-informed fluxes from OCO-2 Version 7r land observations and their uncertainties at continental scales. Additionally, we use in situ measurements to provide a baseline against which to compare the satellite-constrained results. We find that within the ensemble spread, in situ observations, and satellite retrievals constrain a similar global total carbon sink of 3.7±0.5 PgC yr−1, and 1.5±0.6 PgC yr−1 for global land, for the 2015–2016 annual mean. This agreement breaks down in smaller regions, and we discuss the differences between the experiments. Of particular interest is the difference between the different assimilation constraints in the tropics, with the largest differences occurring in tropical Africa, which could be an indication of the global perturbation from the 2015–2016 El Niño. Evaluation of posterior concentrations using TCCON and aircraft observations gives some limited insight into the quality of the different assimilation constraints, but the lack of such data in the tropics inhibits our ability to make strong conclusions there. |
| Programme |
416 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
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Editor |
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| Language |
|
Summary Language |
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Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1680-7316 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7733 |
| Permanent link to this record |
| |
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| |
| Author |
Anna Agustí-Panareda, Michail Diamantakis, Sébastien Massart, Frédéric Chevallier, Joaquín Muñoz-Sabater, Jérôme Barré, Roger Curcoll, Richard Engelen, Bavo Langerock, Rachel M. Law, Zoë Loh, Josep Anton Morguí, Mark Parrington, Vincent-Henri Peuch, Michel Ramonet, Coleen Roehl, Alex T. Vermeulen, Thorsten Warneke, Debra Wunch |
| Title |
Modelling CO2 weather – why horizontal resolution matters |
Type |
Journal |
| Year |
2019 |
Publication |
Atmospheric Chemistry and Physics |
Abbreviated Journal |
|
| Volume |
19 |
Issue |
11 |
Pages |
7347-7376 |
| Keywords |
|
| Abstract |
Climate change mitigation efforts require information on the current greenhouse gas atmospheric concentrations and their sources and sinks. Carbon dioxide (CO2) is the most abundant anthropogenic greenhouse gas. Its variability in the atmosphere is modulated by the synergy between weather and CO2 surface fluxes, often referred to as CO2 weather. It is interpreted with the help of global or regional numerical transport models, with horizontal resolutions ranging from a few hundreds of kilometres to a few kilometres. Changes in the model horizontal resolution affect not only atmospheric transport but also the representation of topography and surface CO2 fluxes. This paper assesses the impact of horizontal resolution on the simulated atmospheric CO2 variability with a numerical weather prediction model. The simulations are performed using the Copernicus Atmosphere Monitoring Service (CAMS) CO2 forecasting system at different resolutions from 9 to 80 km and are evaluated using in situ atmospheric surface measurements and atmospheric column-mean observations of CO2, as well as radiosonde and SYNOP observations of the winds. The results indicate that both diurnal and day-to-day variability of atmospheric CO2 are generally better represented at high resolution, as shown by a reduction in the errors in simulated wind and CO2. Mountain stations display the largest improvements at high resolution as they directly benefit from the more realistic orography. In addition, the CO2 spatial gradients are generally improved with increasing resolution for both stations near the surface and those observing the total column, as the overall inter-station error is also reduced in magnitude. However, close to emission hotspots, the high resolution can also lead to a deterioration of the simulation skill, highlighting uncertainties in the high-resolution fluxes that are more diffuse at lower resolutions. We conclude that increasing horizontal resolution matters for modelling CO2 weather because it has the potential to bring together improvements in the surface representation of both winds and CO2 fluxes, as well as an expected reduction in numerical errors of transport. Modelling applications like atmospheric inversion systems to estimate surface fluxes will only be able to benefit fully from upgrades in horizontal resolution if the topography, winds and prior flux distribution are also upgraded accordingly. It is clear from the results that an additional increase in resolution might reduce errors even further. However, the horizontal resolution sensitivity tests indicate that the change in the CO2 and wind modelling error with resolution is not linear, making it difficult to quantify the improvement beyond the tested resolutions. Finally, we show that the high-resolution simulations are useful for the assessment of the small-scale variability of CO2 which cannot be represented in coarser-resolution models. These representativeness errors need to be considered when assimilating in situ data and high-resolution satellite data such as Greenhouse gases Observing Satellite (GOSAT), Orbiting Carbon Observatory-2 (OCO-2), the Chinese Carbon Dioxide Observation Satellite Mission (TanSat) and future missions such as the Geostationary Carbon Observatory (GeoCarb) and the Sentinel satellite constellation for CO2. For these reasons, the high-resolution CO2 simulations provided by the CAMS in real time can be useful to estimate such small-scale variability in real time, as well as providing boundary conditions for regional modelling studies and supporting field experiments. |
| Programme |
416 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
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Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1680-7316 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
5718 |
| Permanent link to this record |
| |
|
| |
| Author |
Frédéric Chevallier, Marine Remaud, Christopher W. O'Dell, David Baker, Philippe Peylin, Anne Cozic |
| Title |
Objective evaluation of surface- and satellite-driven carbon dioxide atmospheric inversions |
Type |
Journal |
| Year |
2019 |
Publication |
Atmospheric Chemistry and Physics |
Abbreviated Journal |
|
| Volume |
19 |
Issue |
22 |
Pages |
14233-14251 |
| Keywords |
|
| Abstract |
We study an ensemble of six multi-year global Bayesian carbon dioxide (CO2) atmospheric inversions that vary in terms of assimilated observations (either column retrievals from one of two satellites or surface air sample measurements) and transport model. The time series of inferred annual fluxes are first compared with each other at various spatial scales. We then objectively evaluate the small inversion ensemble based on a large dataset of accurate aircraft measurements in the free troposphere over the globe, which are independent of all assimilated data. The measured variables are connected with the inferred fluxes through mass-conserving transport in the global atmosphere and are part of the inversion results. Large-scale annual fluxes estimated from the bias-corrected land retrievals of the second Orbiting Carbon Observatory (OCO-2) differ greatly from the prior fluxes, but are similar to the fluxes estimated from the surface network within the uncertainty of these surface-based estimates. The OCO-2-based and surface-based inversions have similar performance when projected in the space of the aircraft data, but the relative strengths and weaknesses of the two flux estimates vary within the northern and tropical parts of the continents. The verification data also suggest that the more complex and more recent transport model does not improve the inversion skill. In contrast, the inversion using bias-corrected retrievals from the Greenhouse Gases Observing Satellite (GOSAT) or, to a larger extent, a non-Bayesian inversion that simply adjusts a recent bottom-up flux estimate with the annual growth rate diagnosed from marine surface measurements both estimate much different fluxes and fit the aircraft data less. Our study highlights a way to rate global atmospheric inversions. Without any general claim regarding the usefulness of all OCO-2 retrieval datasets vs. all GOSAT retrieval datasets, it still suggests that some satellite retrievals can now provide inversion results that are, despite their uncertainty, comparable with respect to credibility to traditional inversions using the accurate but sparse surface network and that are therefore complementary for studies of the global carbon budget. |
| Programme |
416 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1680-7316 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
3618 |
| Permanent link to this record |
| |
|
| |
| Author |
Shaojie Song, Hélène Angot, Noelle E. Selin, Hubert Gallée, Francesca Sprovieri, Nicola Pirrone, Detlev Helmig, Joël Savarino, Olivier Magand, Aurélien Dommergue |
| Title |
Understanding mercury oxidation and air–snow exchange on the East Antarctic Plateau: a modeling study |
Type |
Journal |
| Year |
2018 |
Publication |
Atmospheric Chemistry and Physics |
Abbreviated Journal |
|
| Volume |
18 |
Issue |
21 |
Pages |
15825-15840 |
| Keywords |
|
| Abstract |
Abstract. Distinct diurnal and seasonal variations of mercury (Hg) have been observed in near-surface air at Concordia Station on the East Antarctic Plateau, but the processes controlling these characteristics are not well understood. Here, we use a box model to interpret the
|
| Programme |
1177,1028 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1680-7316 |
ISBN |
1680-7316 |
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7518 |
| Permanent link to this record |
| |
|
| |
| Author |
Edel, L., J.-f. Rysman, C. Claud, C. Palerme, And C. Genthon |
| Title |
Potential of Passive Microwave around 183 GHz for Snowfall Detection in the Arctic |
Type |
Journal |
| Year |
2019 |
Publication |
Remote sensing |
Abbreviated Journal |
|
| Volume |
11 |
Issue |
19 |
Pages |
2200 |
| Keywords |
snowfall; Arctic; passive microwaves; CloudSat; machine learning |
| Abstract |
This study evaluates the potential use of the Microwave Humidity Sounder (MHS) for snowfall detection in the Arctic. Using two years of colocated MHS and CloudSat observations, we develop an algorithm that is able to detect up to 90% of the most intense snowfall events (snow water path ≥400 g m−2 and 50% of the weak snowfall rate events (snow water path ≤50 g m−2. The brightness temperatures at 190.3 GHz and 183.3 ± 3 GHz, the integrated water vapor, and the temperature at 2 m are identified as the most important variables for snowfall detection. The algorithm tends to underestimate the snowfall occurrence over Greenland and mountainous areas (by as much as −30%), likely due to the dryness of these areas, and to overestimate the snowfall occurrence over the northern part of the Atlantic (by up to 30%), likely due to the occurrence of mixed phase precipitation. An interpretation of the selection of the variables and their importance provides a better understanding of the snowfall detection algorithm. This work lays the foundation for the development of a snowfall rate quantification algorithm. |
| Programme |
1013 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2072-4292 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7718 |
| Permanent link to this record |
| |
|
| |
| Author |
Yan Axel Gómez Coutouly, Kelly E. Graf, Angela K. Gore, Ted Goebel |
| Title |
Little Panguingue Creek: A c. 9600-Year-Old Prehistoric Knapping Workshop in the Nenana Valley, Central Alaska |
Type |
Journal |
| Year |
2019 |
Publication |
PaleoAmerica |
Abbreviated Journal |
|
| Volume |
5 |
Issue |
1 |
Pages |
16-31 |
| Keywords |
Alaska Denali complex microblade technology Nenana Valley Pleistocene–Holocene transition |
| Abstract |
The Nenana Valley near Healy, Alaska, has been the site of many decades of prehistoric archaeological research focused on the late Pleistocene and early Holocene records. New research at the Little Panguingue Creek (LPC) site (HEA-038) provides us with important information about Pleistocene–Holocene human activities in the Nenana Valley foothills. This multi-component site is located on a Healy-aged glacial-outwash terrace, overlooking LPC. A new multi-year excavation program, begun in 2015, revealed a c. 9600 cal yr BP knapping workshop (hammerstones, cores, preforms, cortical spalls, tools, debitage, etc.) with a major microblade component dating from the final phase of the Denali complex, along with an older component dating to c. 11,150 cal yr BP. On-going research at the site will further our understanding of human technological, subsistence, and settlement organization in the Nenana Valley (and beyond) during the Pleistocene/Holocene transition. Here we present preliminary results of work accomplished so far. |
| Programme |
1217 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
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| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
Print ISSN: 2055-5563 Online ISSN: 2055-5571 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7524 |
| Permanent link to this record |
| |
|
| |
| Author |
É Vignon, M.-L. Roussel, I. V. Gorodetskaya, C. Genthon, A. Berne |
| Title |
Present and Future of Rainfall in Antarctica |
Type |
Journal |
| Year |
2021 |
Publication |
Geophysical Research Letters |
Abbreviated Journal |
|
| Volume |
48 |
Issue |
8 |
Pages |
e2020GL092281 |
| Keywords |
|
| Abstract |
While most precipitation in Antarctica falls as snow, little is known about liquid precipitation, although it can have ecological and climatic impacts. This study combines meteorological reports at 10 stations with the ERA5 reanalysis to provide a climatological characterization of rainfall occurrence over Antarctica. Along the East Antarctic coast, liquid precipitation occurs 22 days per year at most and coincides with maritime intrusions and blocking anticyclones. Over the north-western Antarctic Peninsula, rainfall occurs more than 50 days per year on average and the recent summer cooling was accompanied by a decrease of −35 annual rainy days per decade between 1998 and 2015 at Faraday-Vernadsky. Projections from seven latest-generation climate models reveal that Antarctic coasts will experience a warming and more frequent and intense rainfall by the end of the century. Rainfall is expected to impact new regions of the continent, increasing their vulnerability to melting by the preconditioning of surface snow. |
| Programme |
1013,1143 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1944-8007 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7935 |
| Permanent link to this record |
| |
|
| |
| Author |
Mélanie Baroni, Edouard Bard, Jean-Robert Petit, Sophie Viseur |
| Title |
Persistent Draining of the Stratospheric 10Be Reservoir After the Samalas Volcanic Eruption (1257 CE) |
Type |
Journal |
| Year |
2019 |
Publication |
Journal of Geophysical Research: Atmospheres |
Abbreviated Journal |
|
| Volume |
124 |
Issue |
13 |
Pages |
7082-7097 |
| Keywords |
beryllium-10 ice cores Samalas eruption solar reconstructions stratospheric volcanic eruptions |
| Abstract |
More than 2,000 analyses of beryllium-10 (10Be) and sulfate concentrations were performed at a nominal subannual resolution on an ice core covering the last millennium as well as on records from three sites in Antarctica (Dome C, South Pole, and Vostok) to better understand the increase in 10Be deposition during stratospheric volcanic eruptions. A significant increase in 10Be concentration is observed in 14 of the 26 volcanic events studied. The slope and intercept of the linear regression between 10Be and sulfate concentrations provide different and complementary information. Slope is an indicator of the efficiency of the draining of 10Be atoms by volcanic aerosols depending on the amount of SO2 released and the altitude it reaches in the stratosphere. Intercept gives an image of the 10Be production in the stratospheric reservoir, ultimately depending on solar modulation. The Samalas event (1257 CE) stands out from the others as the biggest eruption of the last millennium with the lowest positive slope of all the events. We hypothetize that the persistence of volcanic aerosols in the stratosphere after the Samalas eruption has drained the stratospheric 10Be reservoir for a decade, meaning that solar reconstructions based on 10Be should be considered with caution during this period. The slope of the linear regression between 10Be and sulfate concentrations can also be used to correct the 10Be snow/ice signal of the volcanic disturbance. |
| Programme |
1177,1011 |
| Campaign |
|
| Address |
|
| Corporate Author |
|
Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
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Editor |
|
| Language |
|
Summary Language |
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Original Title |
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| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
2169-8996 |
Medium |
|
| Area |
|
Expedition |
|
Conference |
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| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7857 |
| Permanent link to this record |
| |
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| |
| Author |
Jennifer F. Provencher, Stephanie Borrelle, Richard B. Sherley, Stephanie Avery-Gomm, Peter Hodum, Alex Bond, Heather L. Major, Karen D. McCoy, Rory Crawford, Flemming Merkel, Stephen Votier, Michelle Reynolds, Jeff Hatfield, Dena Spatz, Mark Mallory |
| Title |
Chapter 7 – Seabirds |
Type |
Book Chapter |
| Year |
2019 |
Publication |
World Seas: an Environmental Evaluation (Second Edition) |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
133-162 |
| Keywords |
Climate change Conservation Cumulative effects Disease Fisheries Hunting Marine protected areas Pollution Populations Seabirds |
| Abstract |
Seabirds have a global distribution, are numerous throughout the world’s oceans, and have been used for decades to track and understand changes in the marine environment. They are dependent on a variety of ecosystems, including terrestrial, coastal, and pelagic, and are thus vulnerable to both marine and terrestrial environmental stressors. This chapter examines impacts on seabird populations that occur in the marine environment and are global in nature (touch more than one ocean basin). Both widespread (i.e., climate change induced alterations to marine food webs and sea level rise) and more point-source impacts (i.e., incidental bycatch in fisheries, hunting) are discussed. Additionally, natural occurrences in marine ecosystems (i.e., oceanographic regime shifts, parasites) and issues related to anthropogenic activities (i.e., plastic and oil pollution) are covered. Lastly, we discuss marine protected areas and other efforts aimed at conserving global seabird populations, including colony restoration, community-based research, and international conservation actions. |
| Programme |
333 |
| Campaign |
|
| Address |
|
| Corporate Author |
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Thesis |
Bachelor's thesis |
| Publisher |
|
Place of Publication |
|
Editor |
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| Language |
|
Summary Language |
|
Original Title |
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| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
978-0-12-805052-1 |
Medium |
|
| Area |
|
Expedition |
|
Conference |
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| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7735 |
| Permanent link to this record |
| |
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| |
| Author |
Amandine Gamble, Henri Weimerskirch, Thierry Boulinier |
| Title |
Seabirds blinded by ticks |
Type |
Journal |
| Year |
2020 |
Publication |
Frontiers in Ecology and the Environment |
Abbreviated Journal |
|
| Volume |
18 |
Issue |
6 |
Pages |
322-322 |
| Keywords |
|
| Abstract |
In December 2017, on Possession Island (part of the Crozet Archipelago in the southern Indian Ocean), we observed two breeding white‐chinned petrels (Procellaria aequinoctialis ) with very high levels of tick (Ixodes kerguelenensis ) infestation on both eyes. This degree of infestation was likely responsible for the birds’ death. Although this rare observation may seem anecdotal, it reveals that ticks can be fatal for a long‐lived colonial seabird species, in this case one that is already under pressure from fisheries bycatch and predation by introduced black rats (Rattus rattus ). It also raises questions about the frequency and spatial distribution of such a phenomenon and the conditions that may have been responsible for its occurrence. Such high parasite loads imply high local tick abundances but also a lack of preening by the partner. Could this be linked to the recent death of the partner? Infestations by ticks can affect the health of hosts through blood loss, the injection of toxins, and the transmission of infectious agents. In this instance, the mechanical blocking of eyesight may also have affected the birds’ behavior. The potential impact of climate change on local parasitic infestation levels is another important question. Parasites and diseases can harm endangered species in polar and subpolar areas, and could play critical roles in some circumstances. |
| Programme |
1151 |
| Campaign |
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| Address |
|
| Corporate Author |
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Thesis |
Bachelor's thesis |
| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Summary Language |
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Original Title |
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| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1540-9309 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7797 |
| Permanent link to this record |
