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Data repository to "Modeling ash dispersal from future eruptions of Taupo supervolcano", by S.J. Barker et al.

Metadata Updated: October 26, 2023

This data release contains supplementary material to the Geochemistry, Geophysics, Geosystems article:
"Modeling ash dispersal from future eruptions of Taupo supervolcano", by S.J. Barker et al.
This paper uses Ash3d model simulations to calculate the probability of a given tephra-fall thickness from eruptions of the following sizes: 0.1km3, 1 km3, 5 km3, 50 km3, and 500 km3. All volume cases were modeled with umbrella cloud formation, with additional Ash3d simulations for the case of a 0.1 km3 eruption assuming no development of an umbrella cloud. One thousand model simulations were run for each of these cases. The data release contains model outputs from each of the simulations. The results are packaged in separate zip files, one for each case. Zip files are named for the eruption size modeled (e.g. "0.1km3", "1km3", "5km3" etc.). Other source parameters used for these simulations are described in the paper. Each zip file contains similar contents. Below are the contents of the 0.1km3 directory, for illustration (note that a "d" in the left column indicates a directory). d directory or filename Description

d 0.1km3 Output of 0.1km3 runs 0.1km3/0.1km3_simulations_Kidson_type.txt Percent Kidson types for each simulation 0.1km3/City_thicknesses.txt City thicknesses for each run d 0.1km3/zip_files zip files of output from each run 0.1km3/zip_files/ zip file containing output for run #1 0.1km3/zip_files/ zip file containing output for run #2 0.1km3/zip_files/ zip file containing output for run #3 0.1km3/zip_files/ zip file containing output for run #4 . . .

CONTENTS OF THE FILES xxkm3_simulations_Kidson_type.txt The input_summary.txt files contain a table with each row indicating the percent of each Kidson type for each simulation. The first few lines of the file look like: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Number Eruption start after duration+8 hrs percentage of each Kidson type
1 2 3 4 5 6 7 8 9 10 11 12

1 25-May-2002 16:52:06 26-May-2002 06:52:06 0 0 100 0 0 0 0 0 0 0 0 0 2 11-Aug-1982 03:51:53 11-Aug-1982 17:51:53 0 0 0 0 0 0 0 0 100 0 0 0 3 21-Apr-1989 14:59:53 22-Apr-1989 04:59:53 0 0 0 0 0 0 0 0 36 0 0 64 4 27-Mar-1999 13:21:51 28-Mar-1999 03:21:51 0 0 0 0 0 0 100 0 0 0 0 0 5 05-Jun-2014 17:56:13 06-Jun-2014 07:56:13 0 0 0 0 0 0 0 0 0 0 57 43 . . .
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Each row below the header gives: 1) The run number 2) The eruption start time 3) The end time of the eruption, plus 8 hours (the time over which we assume ash remains aiborne) 4) The percentage of each Kidson type over that period of time

CONTENTS OF THE City_thicknesses.txt FILES Each City_thickness.txt file contains a table with thicknesses of ash (mm) at the main cities for each run. The first few lines look like this: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ City thicknesses for eruptions of 0.1km3 Run Auckland Hamilton Tauranga New Plymouth Napier Wellington

0001 0.000 0.000 0.000 0.000 0.122 0.000 0002 0.000 0.501 3.622 0.000 0.042 0.000 0003 0.000 0.000 0.001 0.000 6.440 0.000 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

CONTENTS OF EACH ZIP FILE Each zip file contains the following: Name Description

ash_arrivaltimes_airports.kmz kmz file showing ash arrival times at airports ash_arrivaltimes_airports.txt Text file listing ash arrival times at airports DepositArrivalTimes.txt Text file listing deposit arrival times at airports DepositFile_ESRI_ASCII.txt ESRI-ASCII gridded text file of deposit thickness (mm) Deposit.kmz kmz file of deposit thickness, can be opened in Google Earth deposit_thickness_mm.gif gif map of deposit thickness (mm)

FORMAT OF DepositFile_ESRI_ASCII.txt This gridded ascii file contains deposit thickness at each node in the model domain. The file contains a header that looks like this:


where NCOLS is the number of columns in the grid NROWS is the number of rows in the grid XLLCORNER is the longitude of the center of the lower-left (most southwest) node YLLCORNER is the latitude of the center of the lower-left (most southwest) node CELLSIZE is the spacing (degrees) between nodes NODATA_VALUE is the value where there are no data
This header is followed by the gridded data, written in 10f10.3 format (10 numbers per row, each number occupying 10 spaces with three digits to the right of the decimal). Each row in the model could occupy several rows in the file due to the limitation of 10
numbers per row in the file. The first row is the southernmost row.

FORMAT OF DepositArrivalTimes.txt This is a gridded ascii file of the arrival time of the deposit at each node in the model. The deposit arrival time is given in hours after the eruption start. The file format is exactly the same as that of DepositFile_ESRI_ASCII.txt. It should be noted that the NODATA_VALUE is incorrectly given as -1.000. The NODATA_VALUE is actually -9999.0. This is the value given at each node if ash never arrived at that node during the simulation.

FORMAT OF ash_arrivaltimes_airports.txt This ascii file contains a table of ash arrival times at airports. An example of the first few lines of one file is: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ARRIVAL TIME OF ASH IN AREA MODELED BY ASH3D simulation using input file: iwf25_Taupo_ESP.inp
Model run date: 2016.12.21, time UTC: 22:46

SOURCE PARAMETERS FOR SIMULATION OF: Taupo run | Pulse start time Duration Plume height volume | UTC hrs km feet km3 | 1 2002-05-25T16:52:00Z 24.00 20.0 65616. 5.00000 |

| |
| |
(Airport code & ) Place name Latitude Longitude | Cloud Arrival Time Duration |
| hrs after |
| date/time UTC start hrs |
Pakatoa, N.Z., New Zealand -37.8069 174.8533 | 2002-05-26T01:47:00Z 8.92 15.95 |
Coromandel, New Zealand -36.7933 175.5167 | 2002-05-26T16:05:00Z 23.22 0.82 |
Whakatane, New Zealand -37.9222 176.9139 | 2002-05-25T16:53:00Z 0.03 26.70 |
Wanganui, New Zealand -39.9667 175.0242 | 2002-05-26T10:34:00Z 17.70 6.50 |
. . . +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ --Line 2 gives the name of the input file used (this was changed to ash3d_input.txt after the simulation); --Line 3 gives the date and time of the simulations --Lines 5-10 summarize the key eruption source parameters --Lines 12 and onward give a table of arrival times, durations, and deposit thicknesses at all airports in the model domain that received ash. The columns in this table are the airport name, latitude, longitude, the time of arrival of the cloud in year-month-day-hour (UTC), the arrival time in hours after the eruption start, the number of hours the cloud remained overhead, the time when ash started falling at a given location (in year-month-day-hour UTC and in hours after the eruption start), the number of hours during which ash fell, the deposit thickness, and the US National Weather Service ranking of deposit thickness (e.g. “trace", “minor”, “substantial”, “heavy”). (The right columns of the table had to be truncated in this explanation).

FORMAT OF KMZ files Files with the .kmz suffix are in zipped keyhole markup language and can be opened in Google Earth(R) Details on the contents of these files can be found on pages 19-22 of Mastin et al. (2013) use of trade names does not imply endorsement of these products

Reference: Mastin, L.G., Randall, M., J., Schwaiger, H. and Denlinger, R., 2013. User's Guide and Reference to Ash3d: A Three-Dimensional Model for Atmospheric Tephra Transport and Deposition, U.S. Geological Survey Open-File Report 2013-1122, pp. 48.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date June 1, 2023
Metadata Updated Date October 26, 2023

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date October 26, 2023
Publisher U.S. Geological Survey
Identifier USGS:5cdd9ed7e4b029273746367a
Data Last Modified 20211118
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 1f2e9c10-ec21-44a6-91ba-8dd38855cf4f
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial 170.22491454044,-42.029219098975,179.40948485258,-34.302967655398
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash 31ce4f4b7353053c7e7dd527ba1c07c46527a732ddb7c7321625ca459013fb51
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": 170.22491454044, -42.029219098975, 170.22491454044, -34.302967655398, 179.40948485258, -34.302967655398, 179.40948485258, -42.029219098975, 170.22491454044, -42.029219098975}

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