Hyp
ers
patia
l Therm
al I
mag
ing
of S
urf
ace H
ydro
therm
al F
eatu
res
at
Pilg
rim H
ot
Sp
ring
s,
Ala
ska u
sing
a s
mall
Unm
anned
Aeria
l Sys
tem
(sU
AS
)
Un
ivers
ity o
f A
lask
a F
airb
an
ks.
*C
orr
esp
on
din
g a
uth
or:
ch
rist
ian
@h
ase
lwim
mer.co
.uk
Ch
risti
an
Ha
se
lwim
me
r* , R
ayja
n W
ilso
n,
Co
rey U
pto
n,
An
up
ma
Pra
ka
sh
, G
we
n H
old
ma
nn
, a
nd
Gre
g W
alk
er
Ac
kn
ow
led
ge
me
nts
Th
is r
ese
arc
h i
s fu
nd
ed
by
the D
ep
art
men
t o
f E
nerg
y G
eo
therm
al
Tech
no
log
ies
Pro
gra
mm
e (
CID
: D
E-E
E0
00
28
46
) an
d t
he A
lask
a E
nerg
y A
uth
ority
Ren
ew
ab
le E
nerg
y F
un
d R
ou
nd
III.
Re
fere
nc
es
1.
Lis
s, S
.A. and
Mo
tyka, R
.J. (1
994) P
ilgrim
Sp
ring
s K
GR
A, S
ew
ard
Penin
sula
, A
lask
a: A
ssess
ment
of fluid
geo
chem
istr
y. G
eo
therm
al R
eso
urc
es
Co
uncil
Transa
ctio
ns,
Vo
l. 18.
2.
Hase
lwim
mer, C
.E., P
rakash
, A
., a
nd
Ho
ldm
ann,
G.
(2011)
Geo
therm
al
Exp
lora
tio
n a
t P
ilgrim
Ho
t S
pring
s, A
lask
a u
sing
airb
orn
e t
herm
al
infr
are
d r
em
ote
sensi
ng
. G
eo
therm
al
Reso
urc
es
Co
uncil
35th
Annual M
eeting
, O
ct
23-2
6, S
an D
ieg
o, C
alif
orn
ia.
3.
Hase
lwim
mer, C
.E.,P
rakash
, A
., a
nd
Ho
ldm
ann,
G., (
2013)
Quantify
ing
the h
eat flux a
nd
outfl
ow
rate
of
ho
t sp
ring
s usi
ng
airb
orn
e t
herm
al
imag
ery
: case
stu
dy
fro
m P
ilgrim
Ho
t S
pring
s,
Ala
ska, R
em
ote
Sensi
ng
of
Envi
ronm
ent,
136, 37-4
6, htt
p:/
/dx.d
oi.o
rg/1
0.1
016/j.r
se.2
013.0
4.0
08.
1. O
ve
rvie
w
• Very
hig
h s
patial
reso
lutio
n (
hyp
ers
patial)
therm
al
rem
ote
sensi
ng
fro
m s
mall
Un
man
ned
Aerial
Sys
tem
s (s
UA
S) has
po
tential t
o c
ontr
ibute
to
map
pin
g a
nd
mo
nito
ring
of
geo
therm
al f
eatu
res.
• sU
AS
dep
loye
d a
t P
ilgrim
Ho
t S
pring
s, A
lask
a w
ith t
he a
im o
f ass
ess
ing
th
e p
ote
ntial
an
d
pra
cticalit
ies
of
usi
ng
su
ch a sy
stem
fo
r g
eo
therm
al
exp
lora
tio
n an
d q
uan
tita
tive
re
sou
rce
ass
ess
ment.
• 4 c
m t
herm
al
imag
ery
pro
vid
ed
an u
np
reced
ente
d c
ap
ab
ility
fo
r m
ap
pin
g h
ot
sprin
gs,
seep
s,
and
th
e s
urf
ace fl
ow
of
geo
therm
al fl
uid
s.
• H
eat
bud
get
mo
del w
as
use
d t
o e
stim
ate
the h
ot
spring
heat flux a
nd
dis
ch
arg
e r
ate
fo
r p
art
of
the g
eo
therm
al
are
a f
rom
the c
alib
rate
d F
LIR
im
ag
ery
, w
hic
h w
as
co
mp
are
d a
gain
st i
n-s
itu
measu
rem
ents
.
4.
Da
ta P
rep
roc
essin
g
• D
ifficu
ltie
s w
ith
p
ho
tog
ram
metr
ic
pro
cessin
g
ap
pro
ach
led
to
u
se
of
sem
i-au
tom
ate
d
mo
saic
kin
g w
ith
PT
Gu
i u
sin
g a
uto
matic e
xp
osu
re
ad
just
men
t.
• M
osaic
m
an
ually
re
gis
tere
d
to
hig
h
reso
luti
on
airb
orn
e v
isib
le im
ag
e u
sin
g A
rcM
ap
.
• F
LIR
TA
U
2
is
un
calib
rate
d
cam
era
: m
osaic
calib
rate
d
usin
g
measu
red
te
mp
era
ture
s o
f
gro
un
d ta
rgets
su
ch
as
ho
t sp
rin
gs
and
b
lack
bo
dy
tarp
s.
5.
Ma
pp
ing
Su
rfa
ce
Hyd
roth
erm
al F
ea
ture
s
• 4
cm
reso
lutio
n t
herm
al
imag
ery
pro
vid
es
very
deta
iled
pic
ture
of
the l
ocatio
ns
and
exte
nts
of
ho
t sp
rin
gs
an
d t
he s
urf
ace o
utfl
ow
of
geo
therm
al fl
uid
s.
6. H
ot
Sp
rin
g H
ea
t F
lux E
sti
ma
tio
n
• H
eat
bud
get
mo
del
use
d t
o e
stim
ate
ho
t sp
ring
heat flux a
nd
outfl
ow
rate
fo
r p
art
of
the
geo
therm
al a
rea.
Heat
bud
get
for
a w
ate
r b
od
y (in
Watt
s) is
exp
ress
ed
as:
• M
od
el
inp
uts
: 1
) F
LIR
im
ag
ery
fo
r h
ot
wate
rs;
2)
atm
osp
heri
c
pro
pert
ies;
3) ave
rag
e t
em
pera
ture
of
no
n-g
eo
therm
al s
urf
ace p
oo
ls.
• sU
AS
FL
IR d
eri
ve
d h
ea
t fl
ux =
0.5
3 M
W,
low
er
than p
revi
ous
resu
lts
fro
m a
irb
orn
e F
LIR
[3] =
0.7
5 a
nd
0.8
6 M
W f
or
2010 a
nd
2011 d
ata
.
• R
esu
lts
co
mp
are
d ag
ain
st
heat flu
x esti
mate
s d
eri
ved
fr
om
in
-sit
u
me
asu
rem
en
ts o
f th
e fl
ow
ra
te (se
e c
ulv
ert
locatio
n o
n p
anel 5
).
• In
-situ fl
ow
rate
use
d t
o c
alc
ula
te a
dve
cti
ve
he
at fl
ux (Ф
adv)
thro
ug
h
the c
ulv
ert
(at
the m
easu
red
wate
r te
mp
) and
to
tal
ho
t sp
rin
g h
ea
t fl
ux
( Фge
o at
the h
ot
spring
tem
p o
f 81˚C
) usi
ng
:
Фad
v/ge
o = ṁ
(hs-h
amb)
w
here
ṁ is
th
e m
ass
flo
w r
ate
(l/s)
an
d h
s, h a
mb
are
en
thalp
ies
of
wate
r (k
J/k
g)
at
the s
prin
g (
in
this
case
fo
r b
oth
th
e m
easu
red
tem
p a
nd
ho
t sp
rin
g t
em
p) an
d a
mb
ien
t w
ate
r te
mp
era
ture
s.
• To
tal
ho
t sp
rin
g h
ea
t fl
ux f
rom
co
mb
ine
d s
UA
S/i
n-s
itu
= s
UA
S F
LIR
-derive
d h
eat flu
x (
0.5
3
MW
) +
calc
ula
ted
ad
vective
flux (0.4
2 M
W) =
0.9
5 M
W
• To
tal h
ot
sp
rin
g h
ea
t fl
ux f
rom
in
-sit
u o
nly
= 2
.93 M
W
• D
iffe
ren
ces
du
e to
p
oo
r calib
ratio
n o
f sU
AS
F
LIR
an
d p
ossib
le u
nd
ere
stim
atio
n
of
FL
IR
ap
pro
ach w
hen c
om
pare
d t
o in
-situ m
easu
rem
ents
.
7. O
utc
om
es
• sU
AS
acq
uired
hyp
ers
patial th
erm
al im
ag
ery
map
ped
cm
-scale
ho
t sp
ring
s and
seep
s, a
nd
th
e
exte
nts
of
ho
t w
ate
r w
ith m
uch g
reate
r d
eta
il th
an a
irb
orn
e t
herm
al i
mag
ery
.
• T
IR im
ag
ery
sho
ws
chang
es
in h
ot
spring
s p
oss
ibly
rela
ted
to
surf
ace h
ydro
log
ical c
on
ditio
ns.
• sU
AS
therm
al
imag
ery
did
no
t p
rovi
de r
elia
ble
est
imate
s o
f th
e h
ot
spring
heat flu
x d
ue t
o
sig
nifi
cant
err
ors
in t
em
pera
ture
calib
ratio
n o
f th
e d
ata
: d
ue t
o u
se o
f uncalib
rate
d c
am
era
.
• T
his
wo
rk h
ighlig
hte
d p
ractical is
sues
to b
e a
dd
ress
ed
befo
re s
UA
S c
an c
om
pete
with
airb
orn
e
therm
al i
mag
ing
such a
s sU
AS
batt
ery
life
, flig
ht
pla
nnin
g,
and
use
of
calib
rate
d s
enso
rs.
3. sU
AS
Da
ta C
olle
cti
on
• A
ery
on
Sco
ut
quad
co
pte
r eq
uip
ped
with F
LIR
TA
U 2
: 640 x
480 p
ixels
co
verin
g 7
.5 -
13
.5 μ
m.
• S
urv
ey flo
wn o
ver
Pilg
rim
Ho
t S
pring
s o
n 2
4/7
/2013:
calm
day
with h
igh
clo
ud
co
ver.
• 10
0m
flyi
ng
heig
ht
= ~
4cm
therm
al i
mag
ery
, flig
ht
lines
pla
nned
aro
und
exte
nt
of
ho
t sp
rin
gs
an
d
therm
al f
eatu
res
map
ped
fro
m ~
1.5
m a
irb
orn
e t
herm
al i
mag
ery
(flo
wn
in 2
01
0).
• ~
20 m
ins
batt
ery
life
(re
quired
fre
quent
retu
rns
to b
ase
), f
ully
auto
no
mo
us
execu
tio
n o
f su
rvey.
• C
oin
cid
en
t co
llectio
n o
f calib
ratio
n d
ata
: ho
t sp
ring
+ t
arp
tem
pera
ture
s, a
tmo
sph
eric v
ariab
les.
2.
Pilg
rim
Ho
t S
pri
ng
s,
Ala
sk
a
• G
eo
therm
al
syst
em
lo
cate
d ~
75
km
NE
of
No
me o
n S
ew
ard
Pen
insu
la.
• S
hallo
w 9
0ºC
aq
uifer
fed
fro
m d
eep
er
rese
rvo
irs
of
at
least
~1
10
-15
0ºC
[1
].
• D
OE
/AE
A f
un
ded
pro
ject
to u
nd
ert
ake
reso
urc
e e
xp
lora
tio
n a
nd
ass
ess
men
t.
• A
irb
orn
e F
LIR
pre
vio
usl
y u
sed
to
map
ho
t sp
ing
s an
d q
uan
tify
heat flu
x a
nd
outfl
ow
rate
: ~
4.7
-7 M
Wth
[2
,3].
01
00
20
05
0M
ete
rs0
30
60
ºC
Ho
t p
oo
ls
Aerial P
ho
tog
rap
h09/1
0/2
010
Ho
t sp
ring
s
Airb
orn
e T
herm
al
09/1
0/2
010
Aerial P
ho
tog
rap
h09/1
0/2
010
Airb
orn
e T
herm
al
09/1
0/2
010
Ala
sk
a
Pilg
rim
Ho
tS
pri
ngs
Le
ft: A
ery
on S
co
ut
quad
co
pte
r
Top
le
ft:
calib
ratio
n t
arg
et
(tem
pera
ture
reco
rded
with F
LIR
and
iButt
on lo
gg
er)
. To
p r
igh
t: t
em
po
rary
weath
er
statio
n
y =
0.0
00
8x +
10
.29
8
20
25
30
35
40
45
50
55
60
65 1
00
00
200
00
30
00
04
00
00
500
00
600
00
70
00
0
Dig
ital N
um
ber
Temperature (ºC)
Ab
ove
: lin
ear
gain
and
off
set
use
d t
o c
alib
rate
the
mo
saic
ked
therm
al i
mag
ery
to
surf
ace t
em
pera
ture
Ba
se
im
ag
e: m
osa
icked
FLIR
TA
U 2
therm
al i
mag
ery
o
verlain
on h
igh r
eso
lutio
n a
erial p
ho
tog
rap
h
Culv
ert
: in
-situ h
ot
spring
flo
w r
ate
05
01
00
25
Mete
rs
10
60
ºC
Churc
h
Calib
ratio
n t
arp
Calib
ratio
n t
arp
Airb
orn
e t
herm
al (
~1.5
m p
ixels
) -
09/1
0/2
010
sUA
S t
herm
al (
~4 c
m p
ixels
) -
07/2
4/2
013
010
Mete
rs
Sm
all
sprin
gs
(cm
scale
)
Seep
in
plu
ng
e p
oo
l
Wate
r su
rface fi
lms
sho
w
sub
tle t
em
p d
iffere
nce
sUA
S t
herm
al
Airb
orn
e t
herm
al
05
Mete
rs
Sp
ring
s no
t se
en
in a
irb
orn
e d
ata
Ho
t sp
ring
s no
t se
en
fro
m s
UA
S d
ata
• D
iffere
nces
in
tem
pera
ture
b
etw
een a
irb
orn
e
and
sU
AS
: p
oo
r calib
ratio
n o
f TA
U
2 d
ata
?
• D
iffere
nces
in
locatio
ns
of
ho
t sp
ring
s: lo
wer
wate
r ta
ble
and
chang
e in
surf
ace
outfl
ow
?
0W
att
s1
3
Ab
ove
: est
imate
d h
ot
spring
heat flux f
or
geo
therm
al
po
ols
(in
units
watt
s/p
ixel)
B4
1B
-03
93
Фto
tal =
Фge
o + Ф
ppt +
Фad
v + Ф
evap
+ Ф
sens
+ Ф
rad + Ф
sun
+ Ф
sky
Фge
o =
heat
inp
ut
fro
m g
eo
therm
al fl
uid
s
Фpp
t =
heat
inp
ut
fro
m p
recip
itatio
n
Фad
v =
heat flu
x f
rom
ad
vectio
n/s
eep
ag
e
Фev
ap
= h
eat
loss f
rom
evap
ora
tio
n
Фse
ns
= h
eat
loss v
ia s
en
sib
le h
eat
tran
sfe
r
Фra
d =
heat
loss b
y r
ad
iatio
n
Фsu
n =
heat
inp
ut
fro
m s
ola
r ra
dia
tio
n
Фsk
y =
h
eat
inp
ut
fro
m a
tmo
sp
heric r
ad
iatio
nФ
geo
Фad
v
Фpp
tФ
sunФ
evapФ
sens
Фra
dФ
sky
