
Metadata for Data_Paleoclimate_Regions.txt

by Fritz et al.

If you use these datasets, please cite:



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DATA SUMMARY

863 lines of 27 columns
Dataset of paleoclimatic localities (mean annual temperatures and/or mean annual precipitation) for focal areas in North America and Europe, and for global stratigraphic stages Aquitanian (some data was also dated to Paleogene but this was not the focus of the data) to Early Pliocene

each row contains a unique combination of Data_ID and stratigraphic stage, but two alternative allocation methods to stratigraphic stages were used (either AutomaticStage, in which case BestStage is NA, or vice versa)
from different compilations of paleobotanical data (Pound et al 2012, Salzmann 2008, Salzmann 2013, Utescher et al 2014)


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DATA EXPLANATIONS: column names and content

- Data_ID: a unique ID for a data point (a MAT and/or MAP value from one spatial location, but may span several stratigraphic stages) - 344 unique entries
- Spatial_ID: a unique ID for a spatial location - 180 unique entries
- latitude: the latitude (decimal) from the source dataset, rounded to 3 decimals
- longitude: the longitude (decimal) from the source dataset, rounded to 3 decimals
- Source: the short reference for the source dataset
- Literature: the literature reference given for the data point in the source dataset
- AutomaticStage: the automatically allocated stratigraphic stage for the data point (entries with a AutomaticStage entry have NA for BestStage dataset, see below for details on stage allocation)
- BestStage: the best allocated stratigraphic stage for the data point (entries with a BestStage entry have NA for AutomaticStage dataset, see below for details on stage allocation)
- Oldest_age: the oldest age (in million years ago) for the data point as given in the source dataset (not available for Salzmann data)
- Youngest_age: the youngest age (in million years ago) for the data point as given in the source dataset (not available for Salzmann data)
- OriginalTimeBin: the original allocation to a stratigraphic stage from the source dataset (not always given)
- AllAutomaticTimeBins: all the stratigraphic stages automatically allocated to the data point strictly based on the given oldest and youngest age (separated by "AND")
- AllBestTimeBins: all the stratigraphic stages manually allocated to the data point, based on the given original stage (OriginalTimeBin) and the given oldest and youngest age (separated by "AND" or "and")
- MAT_C: the mean annual temperature in degrees Celsius (in Utescher, this is the midpoint between the given min_MAT_C and max_MAT_C)
- MAT_error: the error estimate around MAT_C (not always given in Pound, Salzmann; in Utescher, this is the distance from midpoint to given min_MAT_C or max_MAT_C)
- min_MAT_C: the minimum temperature estimate (except for Utescher data, calculated as MAT_C - MAT_error; if no error was given, this is identical to MAT_C)
- max_MAT_C: the maximum temperature estimate (except for Utescher data, calculated as MAT_C + MAT_error; if no error was given, this is identical to MAT_C)
- MAP_mm_yr: the mean annual precipitation in mm per year (in Utescher, this is the midpoint between the given min_MAP_mm_yr or max_MAP_mm_yr)
- MAP_error: the error estimate around MAP_mm_yr (not always given in Pound, Salzmann; in Utescher, this is the distance from midpoint to given min_MAP_mm_yr or max_MAP_mm_yr)
- min_MAP_mm_yr: the minimum precipitation estimate (except for Utescher data, calculated as MAP_mm_yr - MAP_error; if no error was given, this is identical to MAP_mm_yr)
- max_MAP_mm_yr: the maximum precipitation estimate (except for Utescher data, calculated as MAP_mm_yr + MAP_error; if no error was given, this is identical to MAP_mm_yr)
- Location_number: the original location number from the source dataset
- Location_name: the name of the location from the source dataset (in Salzmann, this is the information in the "description_coord" column; in Utescher, this is the pasted from three columns as "ID_Ord.no_Samp.com")
- Pangaea_DOI: the DOI for the Pangaea dataset, only given in Utescher data
- Region: the region the data point falls into; one of six focal regions defined in our paper
- Continent: the continent the data point falls into
- WM_ID: the grid cell ID the data point falls into, matches the column in Data_RegionsGridded.shp


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DATA ORIGINS AND PROCESSING


ASSIGNMENT OF STRATIGRAPHIC STAGES FOR EACH SOURCE DATASET:
We assigned global time bins (i.e. stratigraphic stages) as described in our paper: all Salzmann data points were assigned "Early Pliocene". For the other sources, we assigned stratigraphic stages with automatic allocation based on the min and max age given in the original data sources, and with manual allocation of the best stratigraphic stage based on chronology information and original allocations in the data sources. The table we used is "Data_AgeTablePaleoclimate.txt" (see also methods and SI for further details). For some entries in Utescher et al, the age was not given, so we used the stratigraphic stage given in Utescher for both time allocation schemes if that was given. Entries without data or without any age / stage indication were removed.

We identified and removed duplicate entries and assigned unique Data ID numbers (for a point where MAT or MAP was given, age may be several stages) and unique spatial ID numbers (for a unique spatial location, which may have more than one Data ID numbers associated with it). 


Pound et al 2012:
We extracted 104 data points from 96 spatially unique locations and 74 unique literature sources where either mean annual temperature (MAT in °C) or mean annual precipitation (MAP in mm/year) was given (13 sites only had MAP and 27 sites only had MAT). We then reduced the dataset to 47 data points from 43 locations which fell into our regions and timeframe, and were dated to a maximum of 2 stratigraphic stages in either of the two allocation schemes.
Citation:
Pound, M. J., Haywood, A. M., Salzmann, U. & Riding, J. B. 2012. Global vegetation dynamics and latitudinal temperature gradients during the Mid to Late Miocene (15.97–5.33 Ma). Earth-Sciences Reviews 112, 1-22.

Salzmann 2008; Salzmann 2008, 2013; Salzmann 2013:
We updated and extended data from Salzmann 2008 with the information in 2013. Then we extracted 59 data points from 59 spatially unique locations and 48 unique literature sources where either mean annual temperature (MAT in °C) or mean annual precipitation (MAP in mm/year) was given (10 sites only had MAP and 17 sites only had MAT). We then reduced the dataset to 18 data points from 18 locations which fell into our regions (all Salzmann data were allocated to Early Pliocene).
Citations:
Salzmann, U., Haywood, A. M., Lunt, D. J., Valdes, P. J. & Hill, D. J. 2008. A new global biome reconstruction and data-model comparison for the Middle Pliocene. Global Ecology and Biogeography 17, 432-447.
Salzmann, U., Dolan, A.M., Haywood, A. M., Chan, W.-L., Voss, J., et al. 2013. Challenges in quantifying Pliocene terrestrial warming revealed by data–model discord. Nature Climate Change 3, 969-74.

Utescher et al 2014:
We extracted 535 data points from 264 spatially unique locations and 25 unique literature sources where either mean annual temperature (MAT in °C) or mean annual precipitation (MAP in mm/year) was given (40 sites only had MAT). 27 of these data points were already in Pound, so we overwrote the Pound data with the Utescher data. We then reduced the dataset to 279 data points from 121 locations which fell into our regions and timeframe, and were dated to a maximum of 2 stratigraphic stages in either of the two allocation schemes.
Citation:
Utescher, T. Bruch, A. A., Erdei, B., François, L., Ivanov, D., et al. 2014. The Coexistence Approach—theoretical background and practical considerations of using plant fossils for climate quantification. Paleogeography Paleoclimatology Paleoecology 410, 58-73.

