estimate_exposure: Estimate the rate of climate change for each population.

In LiamDBailey/baileyetal2021: Bird populations most exposed to climate change are less sensitive to climatic variation

Description

For all populations where ECA&D gridded data is available, determine the rate of climate change (mean temperature/year) from 1950 - 2017 in the period identified as the best climate window. We are interested here to show how different populations may be exposed to climate change differently, not necessarily explain exisiting trends; therefore, we are most interested in giving the best estimate of temperature change possible for that location.

Usage

estimate_exposure(SEM_output, return = "SEM_output")

Arguments

SEM_output	Data frame. Output generated by estimate_sensitivity.
return	Should the function return the exposure joined to the SEM output ('SEM_output') or return the full exposure model ('model')

Details

We avoided using time periods of different length for each population as this may lead to a bias in the esimates of climate change exposure. e.g. shorter populations may show more variance in trends due to stochasticity in temperature measurements from year to year. With this in mind, we exclude Vlieland and Sicily from these estimations because we don't have temperature data for the whole 1950 - 2017 period.

This process involves:

• For every population/species, determine dates that correspond to the best window identified using climwin.

• For every year, extract the mean of daily mean temperature during the best climate window.

• Fit a simple linear model (meanT ~ year) and determine the coefficient and standard error of the change in temperature over time within the best climate window for every population.

Value

A data frame. SEM_output with new columns for climate change exposure.

Examples

## Not run: 
#Run for one population

#Extract SEM output (contains information from climwin and SEM coefficients)
HOG_GT_SEM <- readRDS(here::here("data/unshared_files/HOG_GT_SEM.RDS"))

#Determine climate change exposure
estimate_exposure(HOG_GT_SEM)

## End(Not run)

LiamDBailey/baileyetal2021 documentation built on Feb. 10, 2022, 12:34 a.m.