scholarly journals Challenges and benefits of using unstructured citizen science data to estimate seasonal timing of bird migration across large scales

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246572
Author(s):  
Nadja Weisshaupt ◽  
Aleksi Lehikoinen ◽  
Terhi Mäkinen ◽  
Jarmo Koistinen
Keyword(s):  
Large Scale ◽  
Bird Species ◽  
Science Data ◽  
The Past ◽  
Migration Phenology ◽  
Ringing Data ◽  
Valuable Complement ◽  
Species Specific ◽  
Model Approach

Millions of bird observations have been entered on online portals in the past 20 years either as checklists or arbitrary individual entries. While several hundred publications have been written on a variety of topics based on bird checklists worldwide, unstructured non-checklist observations have received little attention and praise by academia. In the present study we tested the suitability of non-checklist data to estimate key figures of large-scale migration phenology in four zones covering the whole of Finland. For that purpose, we analysed 10 years of ornithological non-checklist data including over 400 million. individuals of 115 bird species. We discuss bird- and human-induced effects to be considered in handling non-checklist data in this context and describe applied methodologies to address these effects. We calculated 5%, 50% and 95% percentile dates of spring and autumn migration period for all species in all four zones. For validation purposes we compared the temporal distributions of 43 bird species with migration phenology from standardized long-term ringing data in autumn of which 24 species (56%) showed similar medians. In a model approach, non-checklist data successfully revealed latitudinal migration progression in spring and autumn. Overall, non-checklist data proved to be well suited to determine descriptors of migration phenology in Northern Europe which are challenging to attain by any other currently available means. The effort-to-yield ratio of data processing was commensurate to the outcomes. The unprecedented spatiotemporal coverage makes non-checklist data a valuable complement to current migration databases from bird observatories. The basic concept of the present methodology is applicable to data from other bird portals, if combined with local field ornithological knowledge and literature. Species-specific descriptors of migration phenology can be potentially used in climate change studies and to support echo interpretation in radar ornithology.

scholarly journals High-Resolution, Long-Term Trends in Relative Abundance from Spatial Modeling of Continent-Wide Bird Counts

2018 ◽  
Author(s):  
Timothy D. Meehan ◽  
Nicole L. Michel ◽  
Håvard Rue
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Bird Species ◽  
Current Standard ◽  
Science Data ◽  
Modeling Framework ◽  
American Robin ◽  
Order Of Magnitude ◽  
Community Science

AbstractContinent-wide bird counts by community volunteers provide valuable information about the conservation needs of many bird species. The statistical modeling techniques commonly used to analyze these counts provide robust long-term trend estimates from heterogeneous community science data at regional, national, and continental scales. Here we present a novel modeling framework that increases the spatial resolution of trend estimates, and reduces the computational burden of trend estimation, each by an order of magnitude. We demonstrate the approach with data for the American Robin (Turdus migratorius) from Audubon Christmas Bird Counts conducted between 1966 and 2017, and show that aggregate regional trend estimates from the proposed method align well with those from the current standard method. Thus, it appears that the proposed technique can provide reasonable large-scale trend estimates for users concerned with general patterns, while also providing higher resolution estimates for others examining correlates of abundance trends at finer spatial scales.

scholarly journals Global climatology and trends in convective environments from ERA5 and rawinsonde data

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mateusz Taszarek ◽  
John T. Allen ◽  
Mattia Marchio ◽  
Harold E. Brooks
Keyword(s):  
Large Scale ◽  
Climate Models ◽  
Global Climate ◽  
Convective Available Potential Energy ◽  
Global Climate Models ◽  
Convective Precipitation ◽  
The Past ◽  
The Tropics ◽  
Rawinsonde Data

AbstractGlobally, thunderstorms are responsible for a significant fraction of rainfall, and in the mid-latitudes often produce extreme weather, including large hail, tornadoes and damaging winds. Despite this importance, how the global frequency of thunderstorms and their accompanying hazards has changed over the past 4 decades remains unclear. Large-scale diagnostics applied to global climate models have suggested that the frequency of thunderstorms and their intensity is likely to increase in the future. Here, we show that according to ERA5 convective available potential energy (CAPE) and convective precipitation (CP) have decreased over the tropics and subtropics with simultaneous increases in 0–6 km wind shear (BS06). Conversely, rawinsonde observations paint a different picture across the mid-latitudes with increasing CAPE and significant decreases to BS06. Differing trends and disagreement between ERA5 and rawinsondes observed over some regions suggest that results should be interpreted with caution, especially for CAPE and CP across tropics where uncertainty is the highest and reliable long-term rawinsonde observations are missing.

Trends in the frequency, extent, and severity of spruce budworm outbreaks in eastern Canada

1983 ◽  
Vol 13 (4) ◽  
pp. 539-547 ◽  
Author(s):  
J. R. Blais
Keyword(s):  
20Th Century ◽  
Large Scale ◽  
Spruce Budworm ◽  
Forest Composition ◽  
Eastern Canada ◽  
Clear Cutting ◽  
The Past ◽  
Spruce Stands ◽  
History Of

The history of spruce budworm (Choristoneurafumiferana (Clem.)) outbreaks for the past 200 to 300 years, for nine regions in eastern Canada, indicates that outbreaks have occurred more frequently in the 20th century than previously. Regionally, 21 outbreaks took place in the past 80 years compared with 9 in the preceding 100 years. Earlier infestations were restricted to specific regions, but in the 20th century they have coalesced and increased in size, the outbreaks of 1910, 1940, and 1970 having covered 10, 25, and 55 million ha respectively. Reasons for the increase in frequency, extent, and severity of outbreaks appear mostly attributable to changes caused by man, in the forest ecosystem. Clear-cutting of pulpwood stands, fire protection, and use of pesticides against budworm favor fir–spruce stands, rendering the forest more prone to budworm attack. The manner and degree to which each of these practices has altered forest composition is discussed. In the future, most of these practices are expected to continue and their effects could intensify, especially in regions of recent application. Other practices, including large-scale planting of white spruce, could further increase the susceptibility of forest stands. Forest management, aimed at reducing the occurrence of extensive fir–spruce stands, has been advocated as a long-term solution to the budworm problem. The implementation of this measure at a time when man's actions result in the proliferation of fir presents a most serious challenge to forest managers.

scholarly journals Winners and losers over 35 years of dragonfly and damselfly distributional change in Germany

2020 ◽  
Author(s):  
D.E Bowler ◽  
D. Eichenberg ◽  
K.J. Conze ◽  
F. Suhling ◽  
K. Baumann ◽  
...  
Keyword(s):  
Citizen Science ◽  
Large Scale ◽  
Positive Trend ◽  
Science Data ◽  
Running Water ◽  
Distributional Change ◽  
Novel Approach ◽  
Occupancy Detection ◽  
Declining Species

AbstractRecent studies suggest insect declines in parts of Europe; however, the generality of these trends across different taxa and regions remains unclear. Standardized data are not available to assess large-scale, long-term changes for most insect groups but opportunistic citizen science data is widespread for some taxa. We compiled over 1 million occurrence records of Odonata (dragonflies and damselflies) from different regional databases across Germany. We used occupancy-detection models to estimate annual distributional changes between 1980 and 2016 for each species. We related species attributes to changes in the species’ distributions and inferred possible drivers of change. Species showing increases were generally warm-adapted species and/or running water species while species showing decreases were cold-adapted species using standing water habitats such as bogs. We developed a novel approach using time-series clustering to identify groups of species with similar patterns of temporal change. Using this method, we defined five typical patterns of change for Odonata – each associated with a specific combination of species attributes. Overall, trends in Odonata provide mixed news – improved water quality, coupled with positive impacts of climate change, could explain the positive trend status of many species. At the same time, declining species point to conservation challenges associated with habitat loss and degradation. Our study demonstrates the great value of citizen science data for assessing large-scale distributional change and conservation decision-making.

Improvements in XCO2 accuracy from OCO-2 with the latest ACOS v10 product

2021 ◽  
Author(s):  
Christopher ODell ◽  
Annmarie Eldering ◽  
Michael Gunson ◽  
David Crisp ◽  
Brendan Fisher ◽  
...  
Keyword(s):  
Power Plants ◽  
Large Scale ◽  
Regional Scale ◽  
Surface Fluxes ◽  
Retrieval Algorithm ◽  
The Past ◽  
Tropical Oceans ◽  
Desert Areas ◽  
Global Carbon

<p>While initial plans for measuring carbon dioxide from space hoped for 1-2 ppm levels of accuracy (bias) and precision in the CO<sub>2</sub> column mean dry air mole fraction (XCO<sub>2</sub>), in the past few years it has become clear that accuracies better than 0.5 ppm are required for most current science applications.  These include measuring continental (1000+ km) and regional scale (100s of km) surface fluxes of CO<sub>2</sub> at monthly-average timescales.  Considering the 400+ ppm background, this translates to an accuracy of roughly 0.1%, an incredibly challenging target to hit. </p><p>Improvements in both instrument calibration and retrieval algorithms have led to significant improvements in satellite XCO<sub>2</sub> accuracies over the past decade.  The Atmospheric Carbon Observations from Space (ACOS) retrieval algorithm, including post-retrieval filtering and bias correction, has demonstrated unprecedented accuracy with our latest algorithm version as applied to the Orbiting Carbon Observatory-2 (OCO-2) satellite sensor.   This presentation will discuss the performance of the v10 XCO<sub>2</sub> product by comparisons to TCCON and models, and showcase its performance with some recent examples, from the potential to infer large-scale fluxes to its performance on individual power plants.  The v10 product yields better agreement with TCCON over land and ocean, plus reduced biases over tropical oceans and desert areas as compared to a median of multiple global carbon inversion models, allowing better accuracy and faith in inferred regional-scale fluxes.  More specifically, OCO-2 has single sounding precision of ~0.8 ppm over land and ~0.5 ppm over water, and RMS biases of 0.5-0.7 ppm over both land and water.  Given the six-year and growing length of the OCO-2 data record, this also enables new studies on carbon interannual variability, while at the same time allowing identification of more subtle and temporally-dependent errors.  Finally, we will discuss the prospects of future improvements in the next planned version (v11), and the long-term prospects of greenhouse gas retrievals in the coming years. </p><p> </p>

Quantifying and attributing changes in tropospheric ozone from a combination of satellite measurements and models

2020 ◽  
Author(s):  
Jessica Neu ◽  
Kazuyuki Miyazaki ◽  
Kevin Bowman ◽  
Gregory Osterman
Keyword(s):  
Time Series ◽  
Tropospheric Ozone ◽  
Earth Science ◽  
Satellite Measurements ◽  
Science Data ◽  
The Past ◽  
Long Term Changes ◽  
Earth Science Data

<p>Given the importance of tropospheric ozone as a greenhouse gas and a hazardous pollutant that impacts human health and ecosystems, it is critical to quantify and understand long-term changes in its abundance.  Satellite records are beginning to approach the length needed to assess variability and trends in tropospheric ozone, yet an intercomparison of time series from different instruments shows substantial differences in the net change in ozone over the past decade.  We discuss our efforts to produce Earth Science Data Records of tropospheric ozone and quantify uncertainties and biases in these records.  We also discuss the role of changes in the magnitude and distribution of precursor emissions and in downward transport of ozone from the stratosphere in determining tropospheric ozone abundances over the past 15 years.</p>

scholarly journals Associations between sex, age and species-specific climate sensitivity in migration

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Catherine Jarjour ◽  
Barbara Frei ◽  
Kyle H. Elliott
Keyword(s):  
Temperature Sensitivity ◽  
Significant Variation ◽  
Sliding Window ◽  
Past Century ◽  
Migration Timing ◽  
The Past ◽  
Window Method ◽  
Migration Phenology ◽  
Species Specific ◽  
Window Approach

AbstractWeather often plays a key role in migration timing, and temporal shifts over the past century have been heavily researched and linked to climate change. Much research is however limited by the use of arbitrary time periods during which weather is thought to most influence migration. Here, we compare the classic fixed window method to a novel sliding window approach created to determine periods of temperature sensitivity among organisms, in this case on the migration phenology of nineteen passerine species banded at the McGill Bird Observatory in Montréal, Québec, from 2005 to 2015. We found overall shorter temperature sensitivity windows in the spring than the fall migration and deemed the nonarbitrarily chosen periods of temperature sensitivity to be more useful than the classic fixed window method when used with caution. We also found significant variation in migration timing of 11 species, as well as more cases of male birds arriving in spring prior to females than the reverse. More males departed in fall before females as well. Similarly, on average, older birds arrived in spring ahead of younger individuals and departed prior to younger in the fall.

scholarly journals Was the Little Ice Age more or less El Niño-like than the Medieval Climate Anomaly? Evidence from hydrological and temperature proxy data

2017 ◽  
Vol 13 (3) ◽  
pp. 267-301 ◽  
Author(s):  
Lilo M. K. Henke ◽  
F. Hugo Lambert ◽  
Dan J. Charman
Keyword(s):  
Little Ice Age ◽  
Large Scale ◽  
Global Climate ◽  
Ice Age ◽  
Medieval Climate Anomaly ◽  
Climate Anomaly ◽  
Proxy Data ◽  
The Past ◽  
Proxy Records

Abstract. The El Niño–Southern Oscillation (ENSO) is the most important source of global climate variability on interannual timescales and has substantial environmental and socio-economic consequences. However, it is unclear how it interacts with large-scale climate states over longer (decadal to centennial) timescales. The instrumental ENSO record is too short for analysing long-term trends and variability and climate models are unable to accurately simulate past ENSO states. Proxy data are used to extend the record, but different proxy sources have produced dissimilar reconstructions of long-term ENSO-like climate change, with some evidence for a temperature–precipitation divergence in ENSO-like climate over the past millennium, in particular during the Medieval Climate Anomaly (MCA; AD  ∼  800–1300) and the Little Ice Age (LIA; AD  ∼  1400–1850). This throws into question the stability of the modern ENSO system and its links to the global climate, which has implications for future projections. Here we use a new statistical approach using weighting based on empirical orthogonal function (EOF) to create two new large-scale reconstructions of ENSO-like climate change derived independently from precipitation proxies and temperature proxies. The method is developed and validated using model-derived pseudo-proxy experiments that address the effects of proxy dating error, resolution, and noise to improve uncertainty estimations. We find no evidence that temperature and precipitation disagree over the ENSO-like state over the past millennium, but neither do they agree strongly. There is no statistically significant difference between the MCA and the LIA in either reconstruction. However, the temperature reconstruction suffers from a lack of high-quality proxy records located in ENSO-sensitive regions, which limits its ability to capture the large-scale ENSO signal. Further expansion of the palaeo-database and improvements to instrumental, satellite, and model representations of ENSO are needed to fully resolve the discrepancies found among proxy records and establish the long-term stability of this important mode of climatic variability.

Techniques for optimising long-term, large-scale capture–mark–resighting raptor studies: climb hard, band fast

2013 ◽  
Vol 40 (4) ◽  
pp. 269 ◽  
Author(s):  
Victor G. Hurley ◽  
John G. White ◽  
Raylene Cooke
Keyword(s):  
Selection Criteria ◽  
Large Scale ◽  
Selection Process ◽  
Individual Recognition ◽  
Traditional Approach ◽  
Bird Species ◽  
Window Of Opportunity ◽  
Seasonal Breeding ◽  
Active Nest

Context Efficiency of large-scale capture–mark–recapture (CMR) studies can be improved by developing accurate methods for predicting the window of opportunity in which banding can occur. Aims This research aimed to investigate potential efficiency improvements in a long-term CMR raptor study. The research focussed on: (1) developing selection processes for adopting CMR protocols; (2) testing methods for increasing the number of nestlings successfully banded; and (3) assessing the efficacy of visual identification (VID) bands for collecting re-sight data. Methods Ten selection criteria were developed into a robust CMR-technique selection process and used to assess marking techniques commonly applied to birds. Optimising banding effort by predicting banding dates using two different techniques a priori and a posteriori were tested against a traditional approach to the timing of banding. The cost (in time) to collect resight data at an active nest site was also measured. Key results The CMR selection criteria and parameters provided a transparent selection process and scored metal VID bands the highest for the study design. This provided individual recognition of marked birds up to the expected life-span of 14 years. Both techniques for predicting banding dates improved the proportion of whole clutches banded by 40%. The average time to identify both peregrine falcon adults of a breeding pair wearing VID bands was 30 min. Conclusions The two methods described here for predicting preferred banding dates are of particular value as efficient approaches to banding large numbers of nestlings are key to the success of CMR studies. All of the methods developed in this research can be applied to CMR studies of almost any bird species with a predictable seasonal breeding system. Implications Optimisation and cost effectiveness of CMR studies for seasonal breeding birds can be significantly improved by accurately predicting the window of opportunity in which banding of nestlings can be carried out, and also utilising VID colour bands for rapid collection of recapture data.

scholarly journals A multiscale view of the Phanerozoic fossil record reveals the three major biotic transitions

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Alexis Rojas ◽  
Joaquin Calatayud ◽  
Michał Kowalewski ◽  
Magnus Neuman ◽  
Martin Rosvall
Keyword(s):  
Fossil Record ◽  
Large Scale ◽  
Multilayer Network ◽  
Biotic Crisis ◽  
The Past ◽  
Empirical Estimates ◽  
Multiscale Dynamics ◽  
Ecological Changes ◽  
Fossil Data

AbstractThe hypothesis of the Great Evolutionary Faunas is a foundational concept of macroevolutionary research postulating that three global mega-assemblages have dominated Phanerozoic oceans following abrupt biotic transitions. Empirical estimates of this large-scale pattern depend on several methodological decisions and are based on approaches unable to capture multiscale dynamics of the underlying Earth-Life System. Combining a multilayer network representation of fossil data with a multilevel clustering that eliminates the subjectivity inherent to distance-based approaches, we demonstrate that Phanerozoic oceans sequentially harbored four global benthic mega-assemblages. Shifts in dominance patterns among these global marine mega-assemblages were abrupt (end-Cambrian 494 Ma; end-Permian 252 Ma) or protracted (mid-Cretaceous 129 Ma), and represent the three major biotic transitions in Earth’s history. Our findings suggest that gradual ecological changes associated with the Mesozoic Marine Revolution triggered a protracted biotic transition comparable in magnitude to the end-Permian transition initiated by the most severe biotic crisis of the past 500 million years. Overall, our study supports the notion that both long-term ecological changes and major geological events have played crucial roles in shaping the mega-assemblages that dominated Phanerozoic oceans.

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