=== versions === python 3.12.0 | xarray 2026.9.0 | zarr 3.4.1 | numpy 2.5.4 | pandas 3.0.6 | scipy 1.18.1 | matplotlib 3.11.2 === datacube lookup === catalogue: 3160 datacubes cube: https://its-live-data.s3.amazonaws.com/datacubes/v2-updated-october2024/N60W040/ITS_LIVE_vel_EPSG3413_G0120_X-150000_Y-2250000.zarr composite: https://its-live-data.s3.amazonaws.com/composites/annual/v2-updated-september2025/N60W040/ITS_LIVE_velocity_EPSG3413_120m_X-150000_Y-2250000.zarr EPSG:3413, 80568 image pairs datacube: 80568 image pairs on a 833 x 833 grid of 120 m pixels, chunks (20000, 10, 10) mid_date range: 1984-10-21 to 2025-05-28 composites: 42 annual mosaics, 1984-2025 === annual composites === fastest climatological speed in the cube: 15,195 m/yr pixels with v0 > 1 km/yr: 41,503 (598 km2) === flowline === seed (lon -49.14, lat 69.1) -> EPSG:3413 x=-165213, y=-2282498 flowline: 743 vertices, 89.0 km long; ice-mask edge at x=-196465, y=-2273015; upstream end at x=-114215, y=-2299962 point A: 5 km upstream, x=-191493, y=-2273824, v0=11,810 m/yr point B: 15 km upstream, x=-182234, y=-2276829, v0=10,223 m/yr point C: 30 km upstream, x=-169666, y=-2281882, v0=3,829 m/yr point D: 60 km upstream, x=-142347, y=-2292969, v0=438 m/yr annual composite coverage along the flowline (fraction of vertices with a value): 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 coverage 0.01 0.55 0.35 0.54 0.58 0.63 0.61 0.6 0.62 0.55 0.53 0.59 0.25 0.52 0.52 0.45 0.64 0.63 0.68 0.74 0.65 0.44 0.48 0.77 0.59 0.74 0.69 0.73 0.64 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 === speed along the flowline in selected years (m/yr) === A (5 km) B (15 km) C (30 km) D (60 km) max on line year 1985 6208.0 5527.0 1871.0 NaN 6472.0 1995 5885.0 4435.0 1822.0 NaN 6028.0 2000 10143.0 7583.0 2605.0 NaN 10447.0 2003 14233.0 10616.0 3274.0 363.0 14790.0 2007 15276.0 10554.0 3530.0 376.0 15703.0 2013 14481.0 13767.0 4819.0 438.0 16721.0 2015 13355.0 12647.0 4663.0 455.0 15825.0 2017 13482.0 9451.0 3776.0 452.0 15230.0 2018 11263.0 7997.0 3385.0 431.0 12189.0 2019 9569.0 10523.0 3692.0 419.0 11479.0 2021 13731.0 13190.0 4919.0 429.0 15364.0 2022 10052.0 10866.0 4105.0 423.0 12365.0 2024 10489.0 10436.0 4032.0 420.0 13482.0 2025 11719.0 11291.0 4138.0 415.0 13597.0 === image-pair time series at points === point A: 2,320 image pairs with a value, 1985-03-21 to 2025-05-10 point B: 4,422 image pairs with a value, 1985-04-06 to 2025-05-22 point C: 5,304 image pairs with a value, 1985-03-29 to 2025-05-22 point D: 7,593 image pairs with a value, 1985-06-22 to 2025-05-22 pairs since 2014 dt <= 48 d + error <= 15% + rolling MAD kept % A 1648.0 1493.0 1493.0 1267.0 76.9 B 3873.0 2870.0 2870.0 2784.0 71.9 C 4341.0 4289.0 4191.0 4083.0 94.1 D 7395.0 3027.0 1864.0 1742.0 23.6 sensors among kept pairs at point B: sensor S1A 677 S1B 590 S2B 451 S2A 434 L8 396 L9 236 === seasonal cycle and multi-year change (filtered pairs, 2014 onwards) === km pairs peak month min month seasonal range % 2014 median 2017 median 2024 median point A 5 1267 9 3 54.6 NaN 10025.0 9457.0 B 15 2784 8 4 49.1 11400.0 9114.0 9001.0 C 30 4083 10 5 13.8 4574.0 4000.0 3976.0 D 60 1742 6 11 12.8 444.5 475.0 445.0 point B, calendar-year median of filtered pairs vs annual composite (m/yr): 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 pairs median 11400 10710 11812 9114 8156 9558 8874 13622 9298 9058 9001 9097 mean of monthly medians 11426 12184 13292 9754 8686 10155 11703 13513 11048 11034 10679 9161 months 2 8 7 12 12 12 12 12 12 7 10 4 composite 13374 12647 13500 9451 7997 10523 11699 13190 10866 10874 10436 11291 ITS_LIVE climatological seasonal fit (2014-2024) at the points: A: v0 11,810 m/yr, amplitude 2,104 m/yr (18%), peak on day 259 (~16 Sep) B: v0 10,223 m/yr, amplitude 2,698 m/yr (26%), peak on day 249 (~06 Sep) C: v0 3,829 m/yr, amplitude 239 m/yr (6%), peak on day 267 (~24 Sep) D: v0 438 m/yr, amplitude 2 m/yr (0%), peak on day 172 (~21 Jun) === strain rates (2014-2024 climatology) === point A: longitudinal strain rate +0.015 /yr, effective 0.394 /yr point B: longitudinal strain rate +0.720 /yr, effective 0.871 /yr point C: longitudinal strain rate +0.291 /yr, effective 0.950 /yr point D: longitudinal strain rate +0.009 /yr, effective 0.015 /yr max longitudinal stretching on the flowline: 1.12 /yr at 12.4 km max compression on the flowline: -1.09 /yr at 0.0 km wrote output/flowline_profiles.csv and output/point_timeseries_filtered.csv