Modelling future parasite range expansion with warming climate
We used a series of climate-based models to predict the change in
parasite range with temperature. First, we extracted monthly values for
minimum temperature and maximum temperature for the year 2021-2040 for
four Himalayan sites. We used Madhmaheshwar as a nearby site (30°38′13″N
79°12′58″E) as an alternative to Shokharakh due to non-availability of
data.
We used data from eight global climate models available on WorldClim
(www.worldclim.org) . These
global climate models (GCM) are BCC-CSM2-MR, CNRM-CM6-1, CNRM-ESM2-1,
CanESM5, IPSL-CM6A-LR, MIROC-ES2L, MIROC6, MRI-ESM2-0. We extracted
temperature data for the year 2021-2040 at a spatial resolution of 2.5
minutes to estimate the effect of future climate change on malaria
transmission. A set of scenarios have been chosen to provide a range of
distinct end of century climate change outcomes by the energy modelling
community, which mainly deals with greenhouse gas emission scenarios
driven by different socioeconomic assumptions. We considered the shared
socioeconomic pathway SSP2-4.5, which provides one scenario for global
emissions, consistent with certain assumptions about how socio-economic
trends might evolve in the future. We selected SSP2-4.5 because it
represents a “middle of the road” scenario i.e., the world follows a
path in which social, economic, and technological trends do not shift
markedly from historical patterns.
To extract the minimum temperature and maximum temperature for the year
2021-2040 values, we use the GIS software QGIS (https://www.qgis.org).
We compute the average of predicted monthly mean temperature across all
eight GCM models.