The spatial distribution of TMCFs has been explored by several authors
(Aldrich et al., 1997a; Helmer et al., 2019; Los et al., 2021; Wilson
and Jetz, 2016). However, there is no consensus on zoning or delimiting
its global distribution. The United Nations Environment Programme -
World Conservation Monitoring Center (UNEP-WCMC) efforts have helped
identify 529 TMCFs distributed worldwide (Aldrich et al., 1997a). These
TMCFs were identified by a global directory of experts that described
main sub-national cloud forest regions and sites along with their
latitude and longitude (details in Aldrich et al., 1997b). Here, we used
these TMCFs to select and extract climatic trends associated with these
ecosystems (
Section 2.3 ). Similarly, to evaluate how climatic
trends are affected by the spatial distribution of these ecosystems, we
classified these TMCFs according to their distribution into
biogeographic realms using Dinerstein et al. (2017) layers. This helped
us differentiate TMCFs within five macro-ecological locations:
Neotropical (
n = 254), Palearctic (
n = 90), Indomalayan
(
n = 119), Australasia (
n = 57), and Oceania (
n =1). Eight sites defined by UNEP-WCMC were excluded, given their
inconsistency in their location (Table S1). In addition, we used a mask
of tropical landmasses to compare how trends in low CF at TMCFs differed
from those in other tropical regions. We considered tropical landmasses
as areas between the Tropic of Capricorn and Cancer that fall within
country polygons obtained from Natural Earth (
www.naturalearthdata.com).
We used also country boundaries from Natural Earth to visualize CF
trends among nations.