#Example 2: Assessing Exposure of South American Species
Richness to Climate Change Metrics
For the second example, we evaluated the degree of exposure of South
American species richness among amphibians, birds, and mammals (based on
IUCN data, 2021) to five climate change metrics (Fig.4). The analysis
involved examining the covariation between these metrics and species
richness data. The result was a map comparing richness and projected
dimensions of climate change.
We obtained an historical monthly global time series data spanning from
1901 to 2020 for maximum and minimum temperature, as well as annual
precipitation. Climate data had a spatial resolution of 0.5 degrees and
were sourced from the updated version of the Climate Research Unit’s
database (Harris et al., 2020). Four local climate change metrics were
selected including temporal trend in temperature (Fig.4a), temporal
trend in precipitation (Fig.4b), probability of extreme events (Fig.4c),
and standardized local anomalies (Fig.4d). In addition, one regional
metric, climate change velocity (Fig.4e) was considered.
To assess the complexity of climate change, the five climate change
metrics were combined. Then the combined assessment of climate change
was overlaid on top of the species richness map in South America,
revealing the relationship between the two layers. To determine the
intensity of climate change, the five metrics were rescaled to have a
common range between 0 and 1 before combining them into as a single
raster layer (Fig.2f).