Suitability hotspots
The most suitable areas under current climate conditions were projected
to host up to 64 of the 110 study species, with 11.9% of the total
study area (446,686 km2) projected to be suitable for
at least 30% of the study species (i.e., 33 species; Figure 4). We
detected four contiguous hotspots in all climate models: the lower
Himalayas of north and northeast India, northeastern Pakistan, Nepal,
northern Myanmar, and Bangladesh; the Andaman and Nicobar islands and
southernmost coast of Myanmar; Sri Lanka, covering the entirety of the
island; and south India, in the Western Ghats and along the coasts of
central and southern Maharashtra, Karnataka, and Kerala, and fragmented
regions of southern Karnataka and southern Tamil Nadu, extending to the
southern Nilgiris and Coromandel coast of Tamil Nadu. Additional smaller
hotspots appear in the Ballari-Vijayapura-Hubli region of Karnataka,
India, an area characterised by unique geography and isolated geology
and climate; the highlands west of the Indus valley in northern Pakistan
and eastern Afghanistan; and regions including and immediately north of
Gir National Park, southern Gujarat, India (Figure 4).
Most of these hotspots were projected to remain climatically suitable
for many species by the mid-21st century in all
scenarios, although their extent was generally reduced, particularly in
the lower Himalayas and the Western Ghats hotspots, and projections
suggested northward shifts in the Himalayan regions (Figure 4). In
northern India and northern Pakistan, projected changes reduced
contiguity in projected suitability hotspots (particularly under the
CanESM5 scenarios). In the Western Ghats, declines particularly affected
central Maharashtra and Tamil Nadu. Additionally, the small distinct
hotspots in Ballari-Vijayapura-Hubli were projected to disappear, while
hotspots west of the Indus valley and north of Gir were projected to
expand (Figure 4). Although both climate change models predicted similar
changes, under both HadGEM3 scenarios a marked northward increase in
suitable area in southern Myanmar was projected. Analysis of model
certainty showed a moderate degree of uncertainty around the projected
suitability hotspots in all scenarios, combined with some areas of high
certainty of suitability in the Himalayas and northeastern India, and in
southern India and central-southwestern Sri Lanka (Supplementary
Material 3).