=== versions ===
python 3.12.0 | rasterio 1.5.2 | numpy 2.5.4 | pandas 3.0.6 | matplotlib 3.11.2 | cmcrameri 1.10

=== LiCSAR frames over Svartsengi ===
ascending  016A_02504_162118: 6,427 interferograms online (20150110 to 20260730), heading -11.7 deg, mean incidence 39.2 deg, overpass 18:59 UTC
           using 20250815_20250908 + 20250908_20251002 = 48 days
descending 155D_02484_191814: 2,685 interferograms online (20141121 to 20260203), heading -168.3 deg, mean incidence 39.2 deg, overpass  7:57 UTC
           using 20250813_20250906 + 20250906_20250930 = 48 days

=== showcase interferogram ===
pair 20250908_20260605 (270 days), window 330 x 750 pixels of 0.001 deg (about 49 m x 111 m)
land pixels 51%; median coherence on land 0.40; far-field reference pixels (> 15 km from SENG): 39,223
unwrapped phase at SENG relative to the far field: -40.57 rad = -6.46 fringes = +179.1 mm LOS (one fringe = 27.7 mm)
profile along 63.868 N from -22.725 to the LOS peak at -22.479 E: 8 wrapped-phase jumps counted; unwrapped phase changes by -8.44 cycles = 234 mm

=== cumulative LOS displacement (~48 days) ===
ascending  20250815_20250908: median coherence 0.89, usable 98% of land, ramp removed 15 mm W-E and 20 mm S-N across the window
ascending  20250908_20251002: median coherence 0.87, usable 98% of land, ramp removed 10 mm W-E and 9 mm S-N across the window
ascending  20250815-20251002: max +109.0 mm, SENG +77.8 mm, far-field scatter (std) 4.8 mm, usable 98% of land
descending 20250813_20250906: median coherence 0.85, usable 97% of land, ramp removed 92 mm W-E and 14 mm S-N across the window
descending 20250906_20250930: median coherence 0.83, usable 97% of land, ramp removed 12 mm W-E and 3 mm S-N across the window
descending 20250813-20250930: max +104.0 mm, SENG +89.8 mm, far-field scatter (std) 4.2 mm, usable 97% of land

=== LOS unit vectors at SENG (ground -> satellite) ===
ascending  E -0.555  N -0.123  U +0.823  -> incidence 34.7 deg, look azimuth 77.5 deg
descending E +0.597  N -0.123  U +0.793  -> incidence 37.5 deg, look azimuth 281.7 deg

=== asc + desc decomposition ===
design matrix at SENG [[E_a U_a] [E_d U_d]] = [[-0.555, 0.823], [0.597, 0.793]], condition number 1.40
noise amplification for 1 mm LOS noise: east 1.23 mm, up 0.88 mm
maximum uplift 121.5 mm at -22.459 E, 63.868 N; east-west range -44.0 to +34.8 mm (1st-99th pct)
at SENG: up +103.5 mm, east +12.9 mm
area with > 20 mm uplift: 106 km2

=== GNSS check: SENG (Nevada Geodetic Laboratory, IGS20) ===
3,288 daily solutions 2015-06-26 to 2026-09-26; median sigma E/N/U 0.8/1.1/3.6 mm
ascending  20250815-20251002: GNSS dE +12.1 dN +30.3 dU +112.3 mm -> LOS +81.9 mm; InSAR +77.8 mm; difference -4.1 mm
descending 20250813-20250930: GNSS dE +14.6 dN +33.3 dU +110.6 mm -> LOS +92.3 mm; InSAR +89.8 mm; difference -2.5 mm
showcase pair 20250908_20260605: GNSS predicts +184.0 mm LOS = 6.64 fringes at SENG; the unwrapped interferogram gives +179.1 mm = 6.46
decomposed vs GNSS (14 Aug-1 Oct 2025): up +103.5 vs +108.4 mm, east +12.9 vs +11.9 mm
           InSAR_mm  GNSS_mm
component                   
asc. LOS       77.8     81.9
desc. LOS      89.8     92.3
vertical      103.5    108.4
east           12.9     11.9

=== outputs ===
wrote data/svartsengi_los_2025.npz and output/svartsengi_{los_ascending,los_descending,vertical,east}_mm.tif