Regional rainfall measurements using Passive Aquatic Listener during SPURS field campaign Jie Yang, Stephen C. Riser, Jeffrey A. Nystuen, William E. Asher,

Regional rainfall measurements using Passive Aquatic Listener during SPURS

field campaign

Jie Yang, Stephen C. Riser, Jeffrey A. Nystuen, William E. Asher, and Andrew T. Jessup

2014 Aquarius/SAC-D Science Team Meeting

November 11 – 14, 2014, Seattle, Washington USA

Outline

• Passive Aquatic Listener (PAL) calibration using 6-year Ocean Station PAPA data

• Rainfall measurements using PAL during SPURS1) Rain rate and wind speed results during SPURS

2) Rainfall seasonal and intra-annual variability

3) Implication of rainfall measurements on salinity

• Summary and future work

PAL working mechanism and calibration

Drizzle

Wind only

Light rain followed by heavy downpour

Spectrogram using PAL OSP data

Feb. 11–12, 2008

Jul Aug Sep Oct Nov Dec

4

6

8

10

12

14

16

Date (2007)

Win

d sp

eed

(m

/s)

NoaaPAL

Comparison of wind speed between PAL

and anemometer

Comparison of rainrate

between PAL and in situ rain gauge

Jul Aug Sep Oct Nov Dec0

5

10

15

20

Date (2008)

Ra

in r

ate

(m

m/h

r)

PALNoaa

PAL Rain accumulation using 6-year

OSP data

0 500 1000 1500 20000

500

1000

1500

2000

2500

JD (2007)

RA

(m

m)

PAL SPL1dBPAL mean

Comparison of rain

accumulation between PAL

and in situ rain gauge

0 500 1000 1500 20000

500

1000

1500

2000

2500

JD (2007)

RA

(m

m)

PAL SPL1dBPAL meanNoaa, cutoff 0.1mm/hrNoaa, cutoff 0.4mm/hr

Rainfall measurements during SPURS

Figure: Jessica Anderson

Oct Nov Dec Jan 13 Feb Mar Apr May0

2

4

6

8

10

12

14

Date

Win

d sp

eed

(m

s)

central mooringFloat 7587

Float 7587

Comparison of wind speed between PAL and central mooring

Float 7587 end position: ~200 km away from central mooring

Float 7587

Float 7547

Float 7582

Float 7607

0 100 200 300 4000

100

200

300

400

500

600

700Float 7547

JD (2013)R

A (

mm

)0 100 200 300 400

0

100

200

300

400

500

600

700

RA

(m

m)

Float 7582

JD (2013)

0 100 200 300 4000

100

200

300

400

500

600

700Float 7587

JD (2013)

RA

(m

m)

0 100 200 300 4000

100

200

300

400

500

600

700Float 7607

JD (2013)

RA

(m

m)

0 200 4000

200

400

600

RA

(m

m)

Float 6923

0 200 4000

200

400

600

Float 7547

0 200 4000

200

400

600

Float 7569

0 200 4000

200

400

600

Float 7572

0 200 4000

200

400

600

RA

(m

m)

Float 7582

0 200 4000

200

400

600

Float 7587

0 200 4000

200

400

600

Float 7604

0 200 4000

200

400

600

Float 7607

0 200 4000

200

400

600

RA

(m

m)

Float 7635

JD (2013)0 200 400

0

200

400

600

JD (2013)

Float 7660

0 200 4000

200

400

600

JD (2013)

Float 7681

0 200 4000

200

400

600

JD (2013)

Float 7699

PAL SPL1dB PAL mean 3B42

Comparison of rain accumulation between PAL and

3B42Feb. 2013 – Jan. 2014

Rainfall seasonal and intra-annual variability during SPURS

Sep 12 Dec Mar 13 Jun Sep0

20

40

60

RR

(m

m/h

r)

Day (Start date 9/22/2012)

Sep 13 Dec Mar 14 Jun Sep0

20

40

60

Day (Start date 9/22/2013)

RR

(m

m/h

r)

Implication of rainfall measurements on salinity

Salinity data: central mooring

Summary and future work

• PAL has been established to provide reliable estimates of wind speed and rainrate

• Passive acoustic remote sensing can be used to study the spatial variability and intermittency of rainfall and provide regional maps of the surface wind field

• Advantages of passive acoustic technique over conventional meteorological buoy measurement: autonomous, low-cost, long residence time at sea, real-time data access, and excellent temporal and spatial resolutions

• Future

1) regional map of wind and rain field

2) understanding the data better by combining PAL with S/T data on Argo floats and data that characterize vertical and horizontal advection of water in the region