Supplement of The Cryosphere, 14, 1875–1888, 2020https://doi.org/10.5194/tc-14-1875-2020-supplement© Author(s) 2020. This work is distributed underthe Creative Commons Attribution 4.0 License.

Supplement of

Global Positioning System interferometric reflectometry (GPS-IR)measurements of ground surface elevation changes in permafrost areas innorthern CanadaJiahua Zhang et al.

Correspondence to: Jiahua Zhang (zhangjiahua@link.cuhk.edu.hk)

The copyright of individual parts of the supplement might differ from the CC BY 4.0 License.

1

Figure S1: Ground photos of two GPS stations (a) YELL and (b) REPL (source: https://webapp.geod.nrcan.gc.ca/geod/data-

donnees/cacs-scca.php?locale=en). (a) shows that YELL is located above an undulated and inhomogeneous surface and

surrounded by tall shrubs. This is a negative example and no azimuth range can be selected. (b) shows a positive example that 5 surrounding surface of REPL is open, nearly flat, and relatively homogeneous.

2

Figure S2: Examples of SNR series (left) and their frequency spectrum (right, expressed as reflector height in the x-axis) at the

identified CACS sites. The 2-order polynomial fits of SNR series have been removed. The frequencies have been converted to 10 reflector height by equation (3) in Sect. 2. Each vertical red line in the right panels marks the dominant reflector height.

5 8 11 14 17 20Elevation angle (deg)

-40

-20

0

20

40

SNR

(vol

ts/v

olts

)

0 1 2 3 4 5Reflector height (m)

0

5

10

15

20

Ampl

itude

(vol

ts/v

olts

)

5 8 11 14 17 20Elevation angle (deg)

-60-40-20

0204060

SNR

(vol

ts/v

olts

)

0 1 2 3 4 5Reflector height (m)

0

10

20

30

40

Ampl

itude

(vol

ts/v

olts

)

5 8 11 14 17 20Elevation angle (deg)

-60-40-20

0204060

SNR

(vol

ts/v

olts

)

0 1 2 3 4 5Reflector height (m)

0

10

20

30

40

Ampl

itude

(vol

ts/v

olts

)5 8 11 14 17 20

Elevation angle (deg)

-60-40-20

0204060

SNR

(vol

ts/v

olts

)

0 1 2 3 4 5Reflector height (m)

0

5

10

15

20

25

Ampl

itude

(vol

ts/v

olts

)

IQAL

ALRT

RESO

REPL

5 8 11 14 17 20Elevation angle (deg)

-60-40-20

0204060

SNR

(vol

ts/v

olts

)

0 1 2 3 4 5Reflector height (m)

0

10

20

30

Ampl

itude

(vol

ts/v

olts

)

BAKE

(a) (b)

(c) (d)

(e) (f)

(g) (h)

(i) (j)

3

Figure S3: Time series of tropospheric biases in the estimated reflector height in Resolute Bay in the thaw season (i.e., DOY 192–

250) of 2014. They are the mean values of the tropospheric biases of all satellite tracks, and their standard deviations are indicated 15 by error bars.

195 205 215 225 235 245Day of year in 2014

1

1.3

1.6

1.9

2.2

Trop

osph

eric

bia

s (c

m)

4

Table S1. Receiver and antenna types of the identified GPS stations

ID Receiver type Antenna model Radome Data time span Source

ALRT ASHTECH UZ-

12 ASH701945D_M NONE 2012–2018

https://webapp.geod.nrcan.

gc.ca/geod/datadonnees/ca

csscca.php?locale=en

RESO ASHTECH UZ-

12 ASH700936A_M NONE 2003–2014

REPL TRIMBLE

NETR9 TRM59800.00 NONE 2014–2019

BAKE

TPS NETG3

(before

2013/07/11)

TPS NET-G3A

TPSCR.G3 NONE 2010–2017

IQAL

TPS NETG3

(before

2011/09/12)

TPS NET-G3A

TPSCR.G3 NONE 2010–2019

PONC NOVATEL

GSV4004 NOV702GG NONE 2008–2018

RINEX observation files

HALC NOVATEL

GSV4004 NOV702GG NONE 2008– 2018

IQAC NOVATEL

GSV4004 NOV702GG NONE 2008–2018

RANC SEPT

POLARXS POLANT+_GG NONE 2014–2018

FSIC SEPT

POLARXS POLANT+_GG NONE 2014–2018

FSMC SEPT

POLARXS POLANT+_GG NONE 2014–2018

SANC NOVATEL

GSV4004 NOV702GG NONE 2008–2018