# Comparing ecological relevance of climate velocity indices

## TL;DR

This study compares two methods for calculating climate change velocity and finds one method better predicts how species' ranges shift with climate.

## Contribution

The study demonstrates that the MATCH method outperforms gradient-based methods in predicting species range shifts.

## Key findings

- The MATCH method better describes observed latitudinal and elevation/depth range shifts of species.
- MATCH outperforms gradient-based methods by twice the accuracy in predicting species range shifts.
- Results are based on data from North-American birds and marine species.

## Abstract

Climate change is causing species ranges to shift. Population survival requires species to shift at a sufficient pace to accommodate with climate. However, estimating the velocity of climate change requires an assumption about its direction. This can be done via two alternative methods: the gradient-based methods and the recently introduced Monte-cArlo iTerative Convergence metHod (MATCH). In this work, we investigate how the rates of North-American birds and marine species range shifts correspond to the velocity of climate change (in the latitude, longitude and elevation/depth direction) calculated using either of these methods. These velocities are evaluated against the centroid of each considered species’ observed distribution range, based on the Audubon Christmas Bird Count and the NOAA Global Marine Data databases. We find that the MATCH method better describes the observed latitudinal and elevation/depth range shifts of the species, which is twice the Gradient performance. Developing robust method to evaluate the velocity of species could help in the planning of assisted migration.