SMOS L2 Ocean Salinity

www.argans.co.uk

Level 2 Ocean Salinity

L2OS v611 status

12 February 2014

ARGANS & SMOS L2OS ESL

SMOS L2 Ocean Salinity

www.argans.co.uk

v610 FAT 8/9 October 2013; v611 delivered 12 December 2014

Changes in v611 delivery:

• multi-threading optimisation

• global region defined for AUX_DTBXY_ L1 metrics

• updated galactic maps

• new DAP schema in v61x for faster ESL analysis

Planning:

• v612 bug fix delivery due 28/02/2014

• Tools prototyped for summer delivery

• On-going L1c v61x metrics analysis

• v620...

L2OS v61x status

SMOS L2 Ocean Salinity

www.argans.co.uk

Optimised multi-threading: stress test results

L2OS v611:

• Optimised by skipping coast/land grid points (new Fg_ctrl_ignore flag) & code re-organisation

• Now close to reprocessing 12:1 target

• Detailed analysis in reports

Day t_max nGPs Orbit type

20110503 131.95 125485 A

20110510 157.467 129741 A

20110511 160.683 130591 A

20110512 135.7 131216 D

20110513 130.55 129182 A

20110514 133.4 130819 A

20110515 131.867 129783 D

20110516 133.933 135575 A

20110517 130.217 128767 D

20110518 131.3 134597 A

Averages 137.71 130576

Day t_max nGPs Orbit type

20110509 96.35 130700 A

20110510 96.85 128791 A

20110511 96.25 127306 A

20110512 131.28 127228 A

Averages 105.18 128506

v610 v611

SMOS L2 Ocean Salinity

www.argans.co.uk

Global region for L1 metrics

For each orbit, AUX_DTBXY_ contains per snapshot deltaTB for each region:

List_of_Snapshots Record start

Snapshot_ID Snapshot ID from L1c

Latitude Snapshot boresight latitude

Longitude Snapshot boresight longitude

flags L1c flags for first measurement in snapshot

deltaTB Mean deltaTB (= L1c BT minus forward model 1 BT) for all snapshot measurements within a 0.3 radius circle at xi/eta (0,0).

List_of_Snapshots Record end

Regions can be extracted routinely or for metrics:

SMOS L2 Ocean Salinity

www.argans.co.uk

Updated AUX_GAL2OS

First Stokes/2, old minus new map

Updated GAL2OS with new sky map, without changing model fitting...

SMOS L2 Ocean Salinity

www.argans.co.uk

Updated AUX_GAL_OS

strong sources delta(new – old)

delta(new – old) delta new Sky(PW) – Sky(JT)

Difference between WEF smoothing using PW or JT’s method -0.5K to 2.6K near galactic plane, std 0.21K: only significant when WS < 2m/s (rare), and < other errors in SSS retrrieval

SMOS L2 Ocean Salinity

www.argans.co.uk

Impact of new galactic map on SSS

old GAL_OS & GAL2_OS new GALOS new GAL_OS & GAL2_OS

SMOS L2 Ocean Salinity

www.argans.co.uk

delta SSS (new – old)

old GAL_OS & GAL2_OS delta(GALOS) delta(new GAL_OS & GAL2_OS)

~0.2 to 0.3 psu delta from ~0.1 to 0.2K in GAL2OS

SMOS L2 Ocean Salinity

www.argans.co.uk

GAL_OS applied at low wind speeds

WS delta(new GALOS) count(Fm_gal_noise_error)

WS < 3m/s raises Fm_gal_noise_error in galactic plane

SMOS L2 Ocean Salinity

www.argans.co.uk

n x grid points:

ID, lat/longpriors & sigmas (4 x 14)

posts & sigmas (4 x 14)

oor flags (4 x 27)

fields (8)

m x measurements:

flags (4 x 30)

fieldsdeltaTB (x4)

TBgal (x2)

n x grid points:

ID, lat/longpriors & sigmas (4 x 14)

posts & sigmas (4 x 14)

oor flags (4 x 27)

fields (8)

n x grid points:

IDm x measurements:

snapshot IDxi, etaflags (1 x 30)

fieldsdeltaTB (M1)

TBgal (x2)

Fixed block size grid pointsVariable

block size grid points

Variable block size

measurements

Improved DAP readability

v600 v61x

xi/eta can be used to investigate deltaTBs (but need to read L1c to get BTs)

SMOS L2 Ocean Salinity

www.argans.co.uk

Tools delivery April/May 2014 (see later ppt)

Tuning L2OS v61x with L1 from metrics, & then from reprocessing

• thresholds (outlier detection, RFI, A3TEC, OTT post-processor), L1 flags

• improving & cross-verifying RFI detection

Would be good to see impact of L2OS/L1 v61x before defining L2OS v620

v620 September/October delivery 2014, possible evolution:

• refining A3TEC retrieval – eg land

• improving & cross-verifying RFI detection

• …

L2OS short-term plan