Journal of Remote Sensing,
Год журнала:
2022,
Номер
2022
Опубликована: Янв. 1, 2022
Savannas
cover
a
wide
climatic
gradient
across
large
portions
of
the
Earth’s
land
surface
and
are
an
important
component
terrestrial
biosphere.
have
been
undergoing
changes
that
alter
composition
structure
their
vegetation
such
as
encroachment
woody
increasing
land-use
intensity.
Monitoring
spatial
temporal
dynamics
savanna
ecosystem
(e.g.,
partitioning
herbaceous
vegetation)
function
aboveground
biomass)
is
high
importance.
Major
challenges
include
misclassification
savannas
forests
at
mesic
end
range,
disentangling
contribution
to
biomass,
quantifying
mapping
fuel
loads.
Here,
we
review
current
(2010–present)
research
in
application
satellite
remote
sensing
regional
global
scales.
We
identify
emerging
opportunities
can
help
overcome
existing
challenges.
provide
recommendations
on
how
these
be
leveraged,
specifically
(1)
development
conceptual
framework
leads
consistent
definition
sensing;
(2)
improving
ecologically
relevant
information
soil
properties
fire
activity;
(3)
exploiting
high-resolution
imagery
provided
by
nanosatellites
better
understand
role
landscape
functioning;
(4)
using
novel
approaches
from
artificial
intelligence
machine
learning
combination
with
multisource
observations,
e.g.,
multi-/hyperspectral,
synthetic
aperture
radar
(SAR),
light
detection
ranging
(lidar),
data
plant
traits
infer
potentially
new
relationships
between
biotic
abiotic
components
either
proven
or
disproven
targeted
field
experiments.
Reviews of Geophysics,
Год журнала:
2022,
Номер
60(3)
Опубликована: Апрель 11, 2022
Abstract
Recent
wildfire
outbreaks
around
the
world
have
prompted
concern
that
climate
change
is
increasing
fire
incidence,
threatening
human
livelihood
and
biodiversity,
perpetuating
change.
Here,
we
review
current
understanding
of
impacts
on
weather
(weather
conditions
conducive
to
ignition
spread
wildfires)
consequences
for
regional
activity
as
mediated
by
a
range
other
bioclimatic
factors
(including
vegetation
biogeography,
productivity
lightning)
ignition,
suppression,
land
use).
Through
supplemental
analyses,
present
stocktake
trends
in
burned
area
(BA)
during
recent
decades,
examine
how
relates
its
drivers.
Fire
controls
annual
timing
fires
most
regions
also
drives
inter‐annual
variability
BA
Mediterranean,
Pacific
US
high
latitude
forests.
Increases
frequency
extremity
been
globally
pervasive
due
1979–2019,
meaning
landscapes
are
primed
burn
more
frequently.
Correspondingly,
increases
∼50%
or
higher
seen
some
extratropical
forest
ecoregions
including
high‐latitude
forests
2001–2019,
though
interannual
remains
large
these
regions.
Nonetheless,
can
override
relationship
between
weather.
For
example,
savannahs
strongly
patterns
fuel
production
fragmentation
naturally
fire‐prone
agriculture.
Similarly,
tropical
relate
deforestation
rates
degradation
than
changing
Overall,
has
reduced
27%
past
two
part
decline
African
savannahs.
According
models,
prevalence
already
emerged
beyond
pre‐industrial
Mediterranean
change,
emergence
will
become
increasingly
widespread
at
additional
levels
warming.
Moreover,
several
major
wildfires
experienced
years,
Australian
bushfires
2019/2020,
occurred
amidst
were
considerably
likely
Current
models
incompletely
reproduce
observed
spatial
based
their
existing
representations
relationships
controls,
historical
vary
across
models.
Advances
observation
controlling
supporting
addition
optimization
processes
exerting
upwards
pressure
intensity
weather,
this
escalate
with
each
increment
global
Improvements
better
interactions
climate,
extremes,
humans
required
predict
future
mitigate
against
consequences.
Fire
is
an
integral
component
of
ecosystems
globally
and
a
tool
that
humans
have
harnessed
for
millennia.
Altered
fire
regimes
are
fundamental
cause
consequence
global
change,
impacting
people
the
biophysical
systems
on
which
they
depend.
As
part
newly
emerging
Anthropocene,
marked
by
human-caused
climate
change
radical
changes
to
ecosystems,
danger
increasing,
fires
having
increasingly
devastating
impacts
human
health,
infrastructure,
ecosystem
services.
Increasing
vexing
problem
requires
deep
transdisciplinary,
trans-sector,
inclusive
partnerships
address.
Here,
we
outline
barriers
opportunities
in
next
generation
science
provide
guidance
investment
future
research.
We
synthesize
insights
needed
better
address
long-standing
challenges
innovation
across
disciplines
(i)
promote
coordinated
research
efforts;
(ii)
embrace
different
ways
knowing
knowledge
generation;
(iii)
exploration
science;
(iv)
capitalize
"firehose"
data
societal
benefit;
(v)
integrate
natural
into
models
multiple
scales.
thus
at
critical
transitional
moment.
need
shift
from
observation
modeled
representations
varying
components
climate,
people,
vegetation,
more
integrative
predictive
approaches
support
pathways
toward
mitigating
adapting
our
flammable
world,
including
utilization
safety
benefit.
Only
through
overcoming
institutional
silos
accessing
diverse
communities
can
effectively
undertake
improves
outcomes
fiery
future.
Remote Sensing,
Год журнала:
2022,
Номер
14(4), С. 992 - 992
Опубликована: Фев. 17, 2022
Active
fires
are
devastating
natural
disasters
that
cause
socio-economical
damage
across
the
globe.
The
detection
and
mapping
of
these
require
efficient
tools,
scientific
methods,
reliable
observations.
Satellite
images
have
been
widely
used
for
active
fire
(AFD)
during
past
years
due
to
their
nearly
global
coverage.
However,
accurate
AFD
in
satellite
imagery
is
still
a
challenging
task
remote
sensing
community,
which
mainly
uses
traditional
methods.
Deep
learning
(DL)
methods
recently
yielded
outstanding
results
applications.
Nevertheless,
less
attention
has
given
them
imagery.
This
study
presented
deep
convolutional
neural
network
(CNN)
“MultiScale-Net”
Landsat-8
datasets
at
pixel
level.
proposed
had
two
main
characteristics:
(1)
several
convolution
kernels
with
multiple
sizes,
(2)
dilated
layers
(DCLs)
various
dilation
rates.
Moreover,
this
paper
suggested
an
innovative
Fire
Index
(AFI)
AFD.
AFI
was
added
inputs
consisting
SWIR2,
SWIR1,
Blue
bands
improve
performance
MultiScale-Net.
In
ablation
analysis,
three
different
scenarios
were
designed
multi-size
kernels,
rates,
input
variables
individually,
resulting
27
distinct
models.
quantitative
indicated
model
AFI-SWIR2-SWIR1-Blue
as
variables,
using
sizes
3
×
3,
5
5,
7
simultaneously,
rate
2,
achieved
highest
F1-score
IoU
91.62%
84.54%,
respectively.
Stacking
led
fewer
false
negative
(FN)
pixels.
Furthermore,
our
qualitative
assessment
revealed
models
could
detect
single
pixels
detached
from
large
zones
by
taking
advantage
kernels.
Overall,
MultiScale-Net
met
expectations
detecting
varying
shapes
over
test
samples.
Remote Sensing of Environment,
Год журнала:
2022,
Номер
280, С. 113203 - 113203
Опубликована: Авг. 8, 2022
High
spatial
resolution
commercial
satellite
data
provide
new
opportunities
for
terrestrial
monitoring.
The
recent
availability
of
near-daily
3
m
observations
provided
by
the
PlanetScope
constellation
enables
mapping
small
and
spatially
fragmented
burns
that
are
not
detected
at
coarser
resolution.
This
study
demonstrates,
first
time,
potential
automated
burned
area
mapping.
sensors
have
no
onboard
calibration
or
short-wave
infrared
bands,
variable
overpass
times,
making
them
challenging
to
use
large
area,
automated,
To
help
overcome
these
issues,
a
U-Net
deep
learning
algorithm
was
developed
classify
areas
from
two-date
Planetscope
image
pairs
acquired
same
location.
approach,
unlike
conventional
algorithms,
is
applied
subsets
single
pixels
so
incorporates
as
well
spectral
information.
Deep
requires
amounts
training
data.
Consequently,
transfer
undertaken
using
pre-existing
Landsat-8
derived
reference
train
then
refined
with
smaller
set
Results
across
Africa
considering
659
radiometrically
normalized
sensed
one
day
apart
in
2019
presented.
trained
different
numbers
randomly
selected
256
×
30
pixel
patches
extracted
92
sets
defined
2014
2015.
300,000
Landsat
about
13%
burn
omission
commission
errors
respect
65,000
independent
evaluation
patches.
on
5,000
independently
interpreted
Qualitatively,
able
more
precisely
delineate
boundaries,
including
interiors
unburned
areas,
better
“faint”
indicative
low
combustion
completeness
and/or
sparse
burns.
classification
accuracy
assessed
20
sets,
composed
339.4
million
pixels,
12.29%
12.09%
errors.
dependency
proportion
within
also
examined,
<6.5%
were
less
accurately
classified.
A
regression
analysis
between
grid
cells
classified
against
labelled
maps
showed
high
agreement
(r2
=
0.91,
slope
0.93,
intercept
<0.001),
indicating
largely
compensate
Sustainability,
Год журнала:
2023,
Номер
15(5), С. 4209 - 4209
Опубликована: Фев. 26, 2023
Delhi’s
annual
average
PM2.5
concentration
in
2021–22
was
100
μg/m3—20
times
more
than
the
WHO
guideline
of
5
μg/m3.
This
is
an
improvement
compared
to
limited
information
available
for
pre-CNG-conversion
era
(~30%),
immediately
before
and
after
2010
CWG
(~28%),
mid-2010s
(~20%).
These
changes
are
a
result
continuous
technical
economic
interventions
interlaced
with
judicial
engagement
various
sectors.
Still,
Delhi
ranked
most
polluted
capital
city
world.
air
quality
major
social
political
concern
India,
often
questions
regarding
its
severity
primary
sources,
despite
several
studies
on
topic,
there
consensus
source
contributions.
paper
offers
insight
by
reviewing
influence
urban
growth
since
1990
pollution
levels
sources
evolution
technical,
institutional,
legal
measures
control
emissions
National
Capital
Region
Delhi.