solar_powerTower {GenEst}

Power Tower Example Dataset

Description

An example data set for estimating fatalities from a concentrating solar-thermal (power tower) generation facility.

The simulated site consists of a single tower generating approximately 130 MW. The tower is surrounded by a 250 meter radius circular inner field of heliostats, searched on a weekly schedule. From the inner circle, 18 concentric rings of heliostats 50 meters deep extend to the boundaries of the simulated site. Rings are subdivided into 8 arcs each, with arcs 1-8 immediately adjacent to the central circle. Arcs are search using distance sampling techniques on a weekly schedule, with 29 arcs searched per weekday.

There are two sources of mortality simulated: flux and non-flux (collision or unknown cause).Flux carcasses are generated (weibull) about the tower, with 5% to be found in the outer field. Non-flux mortality is assumed uniform across the site.

The dataset consists of five parts: Data on carcass observations (CO) from inner and outer heliostat searches, field trials for estimating carcass persistence (CP) and searcher efficiency (SE), search schedule (SS), and density weighted proportion (DWP) of area searched at each turbine (which is an area adjustment factor to account for incomplete search coverage).

Usage

solar_powerTower

Format

solar_powerTower is a list with 5 elements:

SE

Searcher efficiency trial data

CP

Carcass persistence trial data

SS

Search schedule parameters

DWP

Density weighted proportion of area searched

CO

Carcass observations

Searcher Efficiency (SE)

$SE is a data frame with each row representing the fate of a single carcass in the searcher efficiency trials. There are columns for:

Season

"winter", "spring", "summer", or "fall"

Size

"bat"; or "lrg", "med", or "sml" bird

Field

indicates carcass placed in inner or outer heliostat field, with levels "inner" or outer.

"Search1",...,"Search5"

fate of carcass on the 1st, 2nd, 3rd, 4th, and 5th search after placement. A value of 1 implies that a carcass was discovered by searchers, 0 implies the carcass was present but not discovered, and any other value is interpreted as "no search" or "carcass not present" and ignored in the model. In this data set, NA indicates that a carcass had been previously discovered and removed from the field. A user may use a variety of values to differentiate different reasons no search was conducted or the carcass was not present. For example, "NS" to indicate the search was not scheduled in that location at that time, or "SC" to indicate the carcass had been removed by scavengers prior to the search.

Carcass Persistence (CP)

$CP is a data frame with each row representing the fate of a single carcass in the carcass persistence trials. There are columns for:

cpID

unique ID for each carcass

Season

"winter", "spring", "summer", or "fall"

Size

"bat"; or "lrg", "med", or "sml" bird

LastPresent, FirstAbsent

endpoints of the interval bracketing the time the carcass was scavenged or otherwise removed from the field. For example, LastPresent = 2.04, FirstAbsent = 3.21 indicates that the carcass was last observed 2.04 days after being placed in the field and was noted missing 3.21 days after being placed. If the precise time of carcass removal is known (e.g., recorded by camera), then LastPresent and FirstAbsent should be set equal to each other. If a carcass persists beyond the last day of the field trial, LastPresent is the last time it was observed and FirstAbsent is entered as Inf or NA.

Search Schedule (SS)

$SS is a data frame with a row for each date an arc at the site was searched, a column of SearchDates, and a column for each arc, and one column at the end for the inner heliostat field, labeled center. In addition, there is a column to indicate the Season. A column with search dates and columns for each distinct area (arcs and center) searched are required. Other columns are optional.

SearchDate

columns of dates on which an arc was searched. Format in this data is "%Y-%m-%d CDT", but time zone (CDT) is optional. A time stamp may be included if desired (e.g., 2018-03-20 02:15:41). Alternatively, \ can be used in place of -.

Season

"winter", "spring", "summer", or "fall" to indicate which season the search was conducted in. Season is optional but may be used as a temporal covariate for fatality estimates.

Density Weighted Proportion (DWP)

$DWP is a data frame with a row for each arc and columns for each carcass size class (labels must match those of the class factors in the carcass observation file). Values represent the density-weighted proportion of the searched area for each size (or the fraction of carcasses that fall in the searched area). In this example, within the inner field (center) observers are unobstructed in ability to discover carcasses, for a DWP of 1. In the outer heliostat field observers walk along transects separated by 50 meters, but the entire area is surveyed, so DWP = 1.

Unit

unique ID for each arc, plus one labeled center for the inner heliostat field. IDs match those used in the $CO data frame and the column names in the $SS data.

bat

DWP associated with size class Bat

sml

DWP associated with size class Small

med

DWP associated with size class Medium

lrg

DWP associated with size class Large

Carcass Observations (CO)

$CO is a data frame with a row for carcass observed in the carcass searches and a number of columns giving information about the given carcass (date found, size, species, etc.)

carcID

unique identifier for each carcass.

Unit

identifier for which unit the given carcass was found at: "arc19", "arc65", etc, for arcs in the outer heliostat field, or "center", indicating the inner heliostat field.

Species

species of the carcass: "BA", "BB", "BC", "BD", "BE", "LA", "LB", "LD", "LE", "MA", "MB", "SA", "SB", "SC", "SD", "SE", "SF", "SG"

Size

size: "bat", "lrg", "med", "sml"

Season

"winter", "spring", "summer", or "fall"

Flux

An optional field indicating whether there Was evidence the animal was killed by flux. "TRUE", or "False".

Field

Optional indicator of whether the animal found in the "inner" or "outer" heliostat field?

Ring

Optional note animals found in the outer heliostat field indicating which concentric ring the carcass was found in.

Distance

Optional note animals found in the outer heliostat field representing the perpendicular distance from the searcher the carcass was discovered at.

DateFound

dates entered in the same format as in $SS$SearchDate. Every date entered here is (and must be) included in the search schedule ($SS$SearchDate

X

Distance in meters from the Western edge of the facility.

Y

Distance in meters from the Southern edge of the facility.

Source

solar_powerTower