of 32
manuscript submitted to
AGU
-
Advances
S
tate
-
dependent
e
cosystem sensitivity to aridity
and water storage deficit
1
compromises
recovery of the tropical South America
carbon balance
from
the
2
2015
-
2016 El Niño
3
Junjie Liu
1,2*
, Kevin Bowman
1,6
, Paul I. Palmer
3,1
, Joanna
Joiner
4
,
Paul
Levine
1
,
A.
Anthony Bloom
1
, Liang Feng
3
,7
,
4
Sassan Saatchi
1
, Michael Keller
5,1
, Marcos Longo
1,†
, David Schimel
1
, Paul O. Wennberg
2
5
6
1.
NASA
Jet Propulsion Laboratory, Caltech, Pasadena, CA, USA.
7
2.
Caltech, Pasadena, CA, USA.
8
3.
National Centre for Ear
th Observation, University of Edinburgh, UK.
9
4.
Goddard Space Flight Center, Greenbelt, MD, USA.
10
5.
USDA Forest Service, International Institute of Tropical Forestry.
11
6.
Joint Institute for Regional Earth System Science and Engineering, University of
12
California, Lo
s Angeles, CA, USA.
13
14
15
Present Address:
Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley,
16
CA, USA.
17
Correspond
ing
author:
J
u
n
j
i
e
L
i
u
(
j
u
n
j
i
e
.
l
i
u
@
j
p
l
.
n
a
s
a
.
g
o
v
)
18
19
Key Points:
20
The total carbon loss from the 2015
-
2016 El Nino over tropical South Americ
a has not
21
recovered by December 2018.
22
The slow recovery is due to the nonlinear response of the carbon cycle to the intense
23
atmospheric aridity coupled with soil water loss.
24
T
he disproportionate impact of
water supply and
demand could compromise resiliency of
25
the Amazonian
to
future
increase
s
in
extreme events
26
27
28
manuscript submitted to
AGU
-
Advances
Abstract
29
During
the
20
15
-
2016 El Ni
ñ
o
,
t
he Amazon
basin
released almost
one
gigato
n
of
carbon
(
Gt
C)
into the atmosphere
30
due to
extreme
temperatures
and drought
.
T
he link between
the
drought impact and recovery
of
the total carbon pools
31
and its
biogeochemical
drivers
i
s
s
t
i
l
l
u
n
k
n
o
w
n
.
W
i
t
h
s
a
t
e
l
l
i
t
e
-
c
o
n
s
t
r
a
i
n
e
d
n
e
t
c
a
r
b
o
n
e
x
c
h
a
n
g
e
a
n
d
i
t
s
c
o
m
p
o
n
e
n
t
32
f
l
u
x
e
s
i
n
c
l
u
d
i
n
g
g
r
o
s
s
p
r
i
m
a
r
y
production
a
n
d
f
i
r
e
e
m
i
s
s
i
o
n
s
,
w
e
show that the total carbon loss
caused by the 2015
-
33
2016 El Niño
ha
d
not recovered
by
Dec 2018
.
In particular,
forest ecosystems over
North
e
astern
(NE)
Amazon
34
suffered
a cumulative
total carbon
loss of ~0.6
Gt
C
through December 2018
driven primarily by
a
suppression of
35
photosynthesis
whereas
Southeastern
savanna
h
carbon
loss was driven in part
due to fire.
We attribute
the slow
36
recovery
to
the non
-
linear response of the carbon cycle to the intense atmospheric aridity coupled with a loss of water
37
supply
during drough
t
that was
concurrent with enhanced land
-
atmosphere coupling
.
We show
the attenuation of
38
carbon uptake is three times
higher
than expected as
a consequence of
a
non
-
linear
response
of the carbon cycle to
39
extreme
atmospheric aridity
,
coupled with
reduced
ground
water suppl
y
.
Our study
fills an important know
l
e
d
ge gap
40
in our understanding
of
the nonlinear response of carbon fluxes to atmospheric aridity and
its impact on regional
post
-
41
drought recovery
as a function of
the vegetation type and
climate
perturbations
.
Our
results suggest that
the
42
disproportionate impact of
water supply and
demand could compromise resiliency of the Amazonian
carbon balance
43
to
future
increase
s
in
extreme events
.
44
45