<s>
BAITSSS	B-Application
(	O
Backward-Averaged	O
Iterative	O
Two-Source	O
Surface	O
temperature	O
and	O
energy	O
balance	O
Solution	O
)	O
is	O
biophysical	O
Evapotranspiration	O
(	O
ET	O
)	O
computer	B-Application
model	I-Application
that	O
determines	O
water	O
use	O
,	O
primarily	O
in	O
agriculture	O
landscape	O
,	O
using	O
remote	O
sensing-based	O
information	O
.	O
</s>
<s>
BAITSSS	B-Application
originated	O
from	O
the	O
research	O
of	O
Ramesh	O
Dhungel	O
,	O
a	O
graduate	O
student	O
at	O
the	O
University	O
of	O
Idaho	O
,	O
who	O
joined	O
a	O
project	O
called	O
"	O
Producing	O
and	O
integrating	O
time	O
series	O
of	O
gridded	O
evapotranspiration	O
for	O
irrigation	O
management	O
,	O
hydrology	O
and	O
remote	B-Application
sensing	I-Application
applications	O
"	O
under	O
professor	O
Richard	O
G	O
.	O
Allen	O
.	O
</s>
<s>
In	O
2012	O
,	O
the	O
initial	O
version	O
of	O
landscape	O
model	O
was	O
developed	O
using	O
the	O
Python	B-Language
IDLE	B-Application
environment	O
using	O
NARR	O
weather	O
data	O
(	O
~	O
32	O
kilometers	O
)	O
.	O
</s>
<s>
as	O
a	O
framework	O
to	O
interpolate	O
ET	O
between	O
the	O
satellite	B-Application
overpass	O
when	O
thermal	O
based	O
surface	O
temperature	O
is	O
unavailable	O
.	O
</s>
<s>
The	O
overall	O
concept	O
of	O
backward	O
averaging	O
was	O
introduced	O
to	O
expedite	O
the	O
convergence	O
process	O
of	O
iteratively	B-Language
solved	O
surface	O
energy	O
balance	O
components	O
which	O
can	O
be	O
time-consuming	O
and	O
can	O
frequently	O
suffer	O
non-convergence	O
,	O
especially	O
in	O
low	O
wind	O
speed	O
.	O
</s>
<s>
In	O
2017	O
,	O
the	O
landscape	O
BAITSSS	B-Application
model	O
was	O
scripted	O
in	O
Python	B-Language
shell	B-Language
,	O
together	O
with	O
GDAL	B-Language
and	O
NumPy	B-Application
libraries	O
using	O
NLDAS	O
weather	O
data	O
(	O
~	O
12.5	O
kilometers	O
)	O
.	O
</s>
<s>
The	O
detailed	O
independent	O
model	O
was	O
evaluated	O
against	O
weighing	O
lysimeter	O
measured	O
ET	O
,	O
infrared	O
temperature	O
(	O
IRT	O
)	O
and	O
net	O
radiometer	O
of	O
drought‐tolerant	O
corn	B-Application
and	O
sorghum	O
at	O
Conservation	O
and	O
Production	O
Research	O
Laboratory	O
in	O
Bushland	O
,	O
Texas	O
by	O
group	O
of	O
scientists	O
from	O
USDA-ARS	O
and	O
Kansas	O
State	O
University	O
between	O
2017	O
and	O
2020	O
.	O
</s>
<s>
Some	O
later	O
development	O
of	O
BAITSSS	B-Application
includes	O
physically	O
based	O
crop	O
productivity	O
components	O
,	O
i.e.	O
</s>
<s>
The	O
majority	O
of	O
remote	B-Application
sensing	I-Application
based	O
instantaneous	O
ET	O
models	O
use	O
evaporative	O
fraction	O
(	O
EF	O
)	O
or	O
reference	O
ET	O
fraction	O
(	O
ETF	O
)	O
,	O
similar	O
to	O
crop	O
coefficients	O
,	O
for	O
computing	O
seasonal	O
values	O
,	O
these	O
models	O
generally	O
lack	O
the	O
soil	O
water	O
balance	O
and	O
Irrigation	O
components	O
in	O
surface	O
energy	O
balance	O
.	O
</s>
<s>
Other	O
limiting	O
factors	O
is	O
the	O
dependence	O
on	O
thermal-based	O
radiometric	O
surface	O
temperature	O
,	O
which	O
is	O
not	O
always	O
available	O
at	O
required	O
temporal	B-General_Concept
resolution	I-General_Concept
and	O
frequently	O
obscured	O
by	O
factors	O
such	O
as	O
cloud	O
cover	O
.	O
</s>
<s>
BAITSSS	B-Application
was	O
developed	O
to	O
fill	O
these	O
gaps	O
in	O
remote	B-Application
sensing	I-Application
based	O
models	O
liberating	O
the	O
use	O
of	O
thermal-based	O
radiometric	O
surface	O
temperature	O
and	O
to	O
serve	O
as	O
a	O
digital	O
crop	O
water	O
tracker	O
simulating	O
high	O
temporal	B-General_Concept
(	O
hourly	O
or	O
sub-hourly	O
)	O
and	O
spatial	O
resolution	O
(	O
30	O
meter	O
)	O
ET	O
maps	O
.	O
</s>
<s>
BAITSSS	B-Application
utilizes	O
remote	B-Application
sensing	I-Application
based	O
canopy	O
formation	O
information	O
,	O
i.e.	O
</s>
<s>
estimation	O
of	O
seasonal	O
variation	O
of	O
vegetation	B-General_Concept
indices	I-General_Concept
and	O
senescence	O
.	O
</s>
<s>
Surface	O
energy	O
balance	O
is	O
one	O
of	O
the	O
commonly	O
utilized	O
approaches	O
to	O
quantify	O
ET	O
(	O
latent	O
heat	O
flux	B-General_Concept
in	O
terms	O
of	O
flux	B-General_Concept
)	O
,	O
where	O
weather	O
variables	O
and	O
vegetation	B-General_Concept
Indices	I-General_Concept
are	O
the	O
drivers	O
of	O
this	O
process	O
.	O
</s>
<s>
BAITSSS	B-Application
adopts	O
numerous	O
equations	O
to	O
compute	O
surface	O
energy	O
balance	O
and	O
resistances	O
where	O
primarily	O
are	O
from	O
Javis	O
,	O
1976	O
,	O
Choudhury	O
and	O
Monteith	O
,	O
1988	O
,	O
and	O
aerodynamic	O
methods	O
or	O
flux-gradient	O
relationship	O
equations	O
with	O
stability	O
functions	O
associated	O
with	O
Monin	O
–	O
Obukhov	O
similarity	O
theory	O
.	O
</s>
<s>
The	O
aerodynamic	O
or	O
flux-gradient	O
equations	O
of	O
latent	O
heat	O
flux	B-General_Concept
in	O
BAITSSS	B-Application
are	O
shown	O
below	O
.	O
</s>
<s>
The	O
flux-gradient	O
equations	O
of	O
sensible	O
heat	O
flux	B-General_Concept
and	O
surface	O
temperature	O
in	O
BAITSSS	B-Application
are	O
shown	O
below	O
.	O
</s>
<s>
Typical	O
Jarvis	O
type-equation	O
of	O
r	O
adopted	O
in	O
BAITSSS	B-Application
is	O
shown	O
below	O
,	O
R	O
is	O
the	O
minimum	O
value	O
of	O
r	O
,	O
LAI	O
is	O
leaf	O
area	O
index	O
,	O
f	O
is	O
fraction	O
of	O
canopy	O
cover	O
,	O
weighting	O
functions	O
representing	O
plant	O
response	O
to	O
solar	O
radiation	O
(	O
F	O
)	O
,	O
air	O
temperature	O
(	O
F	O
)	O
,	O
vapor	O
pressure	O
deficit	O
(	O
F	O
)	O
,	O
and	O
soil	O
moisture	O
(	O
F	O
)	O
each	O
varying	O
between	O
0	O
and	O
1	O
.	O
</s>
<s>
Standard	O
soil	O
water	O
balance	O
equations	O
for	O
soil	O
surface	O
and	O
the	O
root	O
zone	O
are	O
implemented	O
in	O
BAITSSS	B-Application
for	O
each	O
time	O
step	O
,	O
where	O
irrigation	O
decisions	O
are	O
based	O
on	O
the	O
soil	O
moisture	O
at	O
the	O
root	O
zone	O
.	O
</s>
<s>
ET	O
models	O
,	O
in	O
general	O
,	O
need	O
information	O
about	O
vegetation	O
(	O
physical	O
properties	O
and	O
vegetation	B-General_Concept
indices	I-General_Concept
)	O
and	O
environment	O
condition	O
(	O
weather	O
data	O
)	O
to	O
compute	O
water	O
use	O
.	O
</s>
<s>
Primary	O
weather	O
data	O
requirements	O
in	O
BAITSSS	B-Application
are	O
solar	O
irradiance	O
(	O
R	O
)	O
,	O
wind	O
speed	O
(	O
u	O
)	O
,	O
air	O
temperature	O
(	O
T	O
)	O
,	O
relative	O
humidity	O
(	O
RH	O
)	O
or	O
specific	O
humidity	O
(	O
q	O
)	O
,	O
and	O
precipitation	O
(	O
P	O
)	O
.	O
</s>
<s>
Vegetation	B-General_Concept
indices	I-General_Concept
requirements	O
in	O
BAITSSS	B-Application
are	O
leaf	O
area	O
index	O
(	O
LAI	O
)	O
and	O
fractional	O
canopy	O
cover	O
(	O
f	O
)	O
,	O
generally	O
estimated	O
from	O
normalized	O
difference	O
vegetation	B-General_Concept
index	I-General_Concept
(	O
NDVI	O
)	O
.	O
</s>
<s>
Automated	O
BAITSSS	B-Application
can	O
compute	O
ET	O
throughout	O
United	O
States	O
using	O
National	O
Oceanic	O
and	O
Atmospheric	O
Administration	O
(	O
NOAA	O
)	O
weather	O
data	O
(	O
i.e.	O
</s>
<s>
hourly	O
NLDAS	O
:	O
North	O
American	O
Land	O
Data	O
Assimilation	O
system	O
at	O
1/8	O
degree	O
;	O
~	O
12.5	O
kilometers	O
)	O
,	O
Vegetation	B-General_Concept
indices	I-General_Concept
those	O
acquired	O
by	O
Landsat	O
,	O
and	O
soil	O
information	O
from	O
SSURGO	O
.	O
</s>
<s>
BAITSSS	B-Application
generates	O
large	O
numbers	O
of	O
variables	O
(	O
fluxes	B-General_Concept
,	O
resistances	O
,	O
and	O
moisture	O
)	O
in	O
gridded	O
form	O
in	O
each	O
time-step	O
.	O
</s>
<s>
The	O
most	O
commonly	O
used	O
outputs	O
are	O
evapotranspiration	O
,	O
evaporation	B-Algorithm
,	O
transpiration	O
,	O
soil	O
moisture	O
,	O
irrigation	O
amount	O
,	O
and	O
surface	O
temperature	O
maps	O
and	O
time	O
series	O
analysis	O
.	O
</s>
<s>
Feature	O
DescriptionTwo-source	O
energy	O
balanceBAITSSS	O
is	O
a	O
two-source	O
energy	O
balance	O
model	O
(	O
separate	O
soil	O
and	O
canopy	O
section	O
)	O
which	O
is	O
integrated	O
by	O
fraction	O
of	O
vegetation	O
cover	O
(	O
f	O
)	O
based	O
on	O
vegetation	B-General_Concept
indices	I-General_Concept
.	O
</s>
<s>
Two-layers	O
soil	O
water	O
balance	O
BAITSSS	B-Application
simulates	O
soil	O
surface	O
moisture	O
( θ	O
)	O
and	O
root	O
zone	O
moisture	O
( θ	O
)	O
layers	O
are	O
related	O
to	O
the	O
dynamics	O
of	O
evaporative	O
(	O
E	O
)	O
and	O
transpirative	O
(	O
T	O
)	O
flux	B-General_Concept
.	O
</s>
<s>
The	O
soil	O
moisture	O
at	O
both	O
layers	O
is	O
restricted	O
to	O
field	O
capacity	O
( θ	O
)	O
.Surface	O
temperatureBAITSSS	O
iteratively	B-Language
solves	O
surface	O
temperature	O
inverting	O
flux-gradient	O
equations	O
of	O
H	O
at	O
the	O
soil	O
surface	O
(	O
subscript	O
s	O
)	O
(	O
T	O
)	O
and	O
canopy	O
level	O
(	O
subscript	O
c	O
)	O
(	O
T	O
)	O
for	O
each	O
time	O
step	O
using	O
continuous	O
weather	O
variables	O
and	O
surface	O
roughness	O
defined	O
by	O
vegetation	B-General_Concept
Indices	I-General_Concept
.	O
</s>
<s>
Ground	O
heat	O
flux	B-General_Concept
of	O
soil	O
BAITSSS	B-Application
estimates	O
ground	O
heat	O
flux	B-General_Concept
(	O
G	O
)	O
of	O
soil	O
surface	O
based	O
on	O
sensible	O
heat	O
flux	B-General_Concept
(	O
H	O
)	O
or	O
net	O
radiation	O
(	O
R	O
)	O
of	O
soil	O
surface	O
and	O
neglects	O
G	O
on	O
vegetated	O
surface.TranspirationVariable	O
canopy	O
conductance	O
in	O
terms	O
of	O
canopy	O
resistance	O
(	O
r	O
)	O
,	O
based	O
on	O
the	O
Jarvis-type	O
algorithm	O
is	O
used	O
to	O
compute	O
transpiration.EvaporationEvaporation	O
(	O
E	O
)	O
in	O
BAITSSS	B-Application
is	O
computed	O
based	O
on	O
soil	O
resistance	O
(	O
r	O
)	O
and	O
soil	O
water	O
content	O
in	O
soil	O
surface	O
layer	O
(	O
upper	O
100	O
millimeters	O
of	O
soil	O
water	O
balance	O
)	O
.IrrrigationBAITSSS	O
simulates	O
irrigation	O
(	O
I	O
)	O
in	O
agricultural	O
landscapes	O
by	O
mimicking	O
a	O
tipping-bucket	O
approach	O
(	O
applied	O
to	O
surface	O
as	O
sprinkler	O
or	O
sub-surface	O
layer	O
as	O
drip	O
)	O
,	O
using	O
Management	O
Allowed	O
Depletion	O
(	O
MAD	O
)	O
,	O
and	O
soil	O
water	O
content	O
regimes	O
at	O
rooting	O
depth	O
(	O
lower	O
100-2000	O
millimeters	O
of	O
soil	O
layer	O
)	O
.Biomass	O
and	O
YieldBAITSSS	O
computes	O
above	O
biomass	O
from	O
transpiration	O
efficiency	O
normalized	O
by	O
vapor	O
pressure	O
deficit	O
and	O
grain	O
fraction	O
by	O
empirical	O
function	O
of	O
biomass	O
.	O
</s>
<s>
BAITSSS	B-Application
was	O
implemented	O
to	O
compute	O
ET	O
in	O
southern	O
Idaho	O
for	O
2008	O
,	O
and	O
in	O
northern	O
California	O
for	O
2010	O
.	O
</s>
<s>
It	O
was	O
used	O
to	O
calculate	O
corn	B-Application
and	O
sorghum	O
ET	O
in	O
Bushland	O
,	O
Texas	O
for	O
2016	O
,	O
and	O
multiple	O
crops	O
in	O
northwest	O
Kansas	O
for	O
20132017	O
.	O
</s>
<s>
BAITSSS	B-Application
has	O
been	O
widely	O
discussed	O
among	O
the	O
peers	O
around	O
the	O
world	O
,	O
including	O
Bhattarai	O
et	O
al	O
.	O
</s>
<s>
United	O
States	O
Senate	O
Committee	O
on	O
Agriculture	O
,	O
Nutrition	O
and	O
Forestry	O
listed	O
BAITSSS	B-Application
in	O
its	O
climate	O
change	O
report	O
.	O
</s>
<s>
BAITSSS	B-Application
was	O
also	O
covered	O
by	O
articles	O
in	O
Open	O
Access	O
Government	O
,	O
Landsat	O
science	O
team	O
,	O
Grass	O
&	O
Grain	O
magazine	O
,	O
National	O
Information	O
Management	O
&	O
Support	O
System	O
(	O
NIMSS	O
)	O
,	O
terrestrial	O
ecological	O
models	O
,	O
key	O
research	O
contribution	O
related	O
to	O
sensible	O
heat	O
flux	B-General_Concept
estimation	O
and	O
irrigation	O
decision	O
in	O
remote	B-Application
sensing	I-Application
based	O
ET	O
models	O
.	O
</s>
<s>
In	O
September	O
2019	O
,	O
the	O
Northwest	O
Kansas	O
Groundwater	O
Management	O
District	O
4	O
(	O
GMD	O
4	O
)	O
along	O
with	O
BAITSSS	B-Application
received	O
national	O
recognition	O
from	O
American	O
Association	O
for	O
the	O
Advancement	O
of	O
Science	O
(	O
AAAS	O
)	O
.	O
</s>
<s>
AAAS	O
discussed	O
the	O
development	O
and	O
use	O
of	O
intricate	O
ET	O
model	O
BAITSSS	B-Application
and	O
Dhungel	O
's	O
and	O
other	O
scientists	O
efforts	O
supporting	O
effective	O
use	O
of	O
water	O
in	O
Sheridan	O
County	O
,	O
Kansas	O
.	O
</s>
<s>
Furthermore	O
,	O
Upper	O
Republican	O
Regional	O
Advisory	O
Committee	O
of	O
Kansas	O
(	O
June	O
2019	O
)	O
and	O
GMD	O
4	O
discussed	O
possible	O
benefit	O
and	O
utilization	O
of	O
BAITSSS	B-Application
for	O
managing	O
water	O
use	O
,	O
educational	O
purpose	O
,	O
and	O
cost-share	O
.	O
</s>
<s>
Dhungel	O
et	O
al.	O
,	O
2020	O
,	O
combined	O
with	O
field	O
crop	O
scientists	O
,	O
systems	O
analysts	O
,	O
and	O
district	O
water	O
managers	O
,	O
applied	O
BAITSSS	B-Application
at	O
the	O
district	O
water	O
management	O
level	O
focusing	O
on	O
seasonal	O
ET	O
and	O
annual	O
groundwater	O
withdrawal	O
rates	O
at	O
Sheridan	O
6	O
(	O
SD-6	O
)	O
Local	O
Enhanced	O
Management	O
Plan	O
(	O
LEMA	O
)	O
for	O
five	O
years	O
period	O
(	O
2013-2017	O
)	O
in	O
northwest	O
,	O
Kansas	O
,	O
United	O
States	O
.	O
</s>
<s>
BAITSSS	B-Application
simulated	O
irrigation	O
was	O
compared	O
to	O
reported	O
irrigation	O
as	O
well	O
as	O
to	O
infer	O
deficit	O
irrigation	O
within	O
water	O
right	O
management	O
units	O
(	O
WRMU	O
)	O
.	O
</s>
<s>
The	O
in-season	O
water	O
supply	O
was	O
compared	O
to	O
BAITSSS	B-Application
simulated	O
ET	O
as	O
well-watered	O
crop	O
water	O
condition	O
.	O
</s>
<s>
A	O
study	O
related	O
to	O
ET	O
uncertainty	O
associated	O
with	O
ET	O
hysteresis	O
(	O
Vapor	O
pressure	O
and	O
net	O
radiation	O
)	O
were	O
conducted	O
using	O
lysimeter	O
,	O
Eddy	O
covariance	O
(	O
EC	O
)	O
,	O
and	O
BAITSSS	B-Application
model	O
(	O
point-scale	O
)	O
in	O
an	O
advective	O
environment	O
of	O
Bushland	O
,	O
Texas	O
.	O
</s>
<s>
Results	O
indicated	O
that	O
the	O
pattern	O
of	O
hysteresis	O
from	O
BAITSSS	B-Application
closely	O
followed	O
the	O
lysimeter	O
and	O
showed	O
weak	O
hysteresis	O
related	O
to	O
net	O
radiation	O
when	O
compared	O
to	O
EC	O
.	O
</s>
<s>
However	O
,	O
both	O
lysimeter	O
and	O
BAITSSS	B-Application
showed	O
strong	O
hysteresis	O
related	O
to	O
VPD	O
when	O
compared	O
to	O
EC	O
.	O
</s>
<s>
Simulation	O
of	O
hourly	O
ET	O
at	O
30	O
m	O
spatial	O
resolution	O
for	O
seasonal	O
time	O
scale	O
is	O
computationally	O
challenging	O
and	O
data-intensive	B-Operating_System
.	O
</s>
