Intercomparison of Appeal Information and WSR-88D Tempest Incorporated Precipitation

1846 days ago, 500 views
PowerPoint PPT Presentation
Bolsters nearby climate and atmosphere research at the GHCC. accept climate radar and ... Stage I - incorporated precipitation from neighborhood radar utilizing standard or tropical Z-R ...

Presentation Transcript

Slide 1

Intercomparison of CHARM Data and WSR-88D Storm Integrated Rainfall Gary Jedlovec (NASA), Paul Meyer (NASA), Anthony Guillory (NASA), Ashutosh Limaye (USRA), Global Hydrology and Climate Center,Huntsville, Alabama and Keith Stellman (NOAA/NWS), LMRFC, Slidell, Louisiana Goal: Produce a fine scale hourly precipitation item by consolidating radar and exceptional rain gage estimations. Diagram: CHARM rain gage organize NWS WSR-88D HDP items Case concentrate on intercomparison Data mix Discussion

Slide 2

COOPERATIVE HUNTSVILLE-AREA RAINFALL MEASUREMENT NETWORK (CHARM) Gage OWNERSHIP MAP 80km JANUARY 2002 Local precipitation arrange ( est. 1/2001) 110 destinations in Huntsville & Madison County, AL NASA, Army, USGS, and NWS locales and climate fans Daily precipitation sums (1200UTC reports) 3600 km 2 scope (1 gage for every 6x6 km) Primarily 4" manual gages (70%) with staying (30%) manual or mechanized tipping pail (6" and 8") Plans to grow to 200 stations by 2003 4x4 km normal separating twice day by day manual perceptions 1 minute information from 40 computerized locales huge picture Supports nearby climate and atmosphere explore at the GHCC approve climate radar and lightning information from satellites screen spatial circulations of precipitation for displaying exercises different satellite remote detecting investigations of soil dampness and vitality fluxes

Slide 3

TYPES OF RAIN Gages USED IN CHARM 4" non-recording "all-climate" plastic 6", 8" non-recording (metal) 6", 8" tipping basin – recorded electronically 6", 8" recording week by week paper outlines

Slide 4

CHARM Data Analysis June 4-5, 2001 Case Study Isolated overwhelming rainstorm travels through the CHARM organize Slow west-to-east development over Huntsville Rainfall aggregates reported at 1200UTC for the first 24h . For June 4-5, the 24h sums catch just this tempest occasion. Unpredictably separated gage information (from 200m to 10 km) were unbiasedly examined to a uniform lattice to make the picture. Some smoothing of greatest qualities is inescapable. Max= 2.96" Max=2.73" Maximum rain rate of around 2 in/hr Details : Strong north-south slope on either side of the tempest track. Width of substantial precipitation region is around 10 km Maximum of 2.96" on east of area, auxiliary max (2.73") in the western portion of system huge picture

Slide 5

NASHVILLE RADAR HYTOP RADAR Hourly Digital Precipitation Product NWS workplaces deliver their own particular precipitation gauges from their nearby WSR-88D radar. The Nashville and Hytop (upper east of Huntsville) radars caught this tempest occasion. Figures show storm sums (aggregate of hourly item over tempest lifetime ~ 4-6 hours). Same general structure Nashville radar delineates more serious and far reaching precipitation Radar alignment, rise, check examples and separation from tempest may all add to the distinction. 4-5" ~3"

Slide 6

NWS HDP Products Example of stage III radar item for June 4, 2001 over Northern Alabama. Hourly stage III item summed from 2100 – 0300 UTC. Arrange I - coordinated precipitation from nearby radar utilizing standard or tropical Z-R connections on 4 km matrix – reliant on Z-R relationship utilized Stage II - balanced stage I item for inclination utilizing neighborhood (hourly) rain gages Stage III - blend of stage II HDP from individual radars to create a provincial precipitation appraise insignificant predisposition because of mis-alignment and distinctive Z-R, nearby and occasional conformities local coherence and consistency Rainfall (cm) Note the double precipitation most extreme in the stage III radar item compares pleasantly both in position and greatness to the CHARM information. Stellman et al. 2001 (Wea. Fore.) CHARM

Slide 7

Stage III versus CHARM Resolution issues will influence correlation Radar: radar volume – fluctuates with separation 4km matrix cells – self-assertive determination Rain gage: point estimation – microscale changeability of precipitation most noteworthy in convective circumstances numerous rain gages for every framework cell (a solitary best examination utilized as a part of investigation beneath) ALL POINTS MD = 0.19" SD = 0.50" Comparison demonstrates next to zero inclination (0.19") between CHARM estimations and radar gauges. Disseminate is extensive particularly for sums > 1.00". <1" > 1" MD = 0.21" 0.17" SD = 0.15" 0.60"

Slide 8

Combined Stage III and CHARM Data Can time-nonstop stage III information items be utilized to enhance 24h precipitation gauges from spatially thick CHARM rain gage arrange? Change hourly stage III information utilizing CHARM 24h information Assume rain gage (24h aggregate) is right and accept (radar – rain gage) predisposition is consistent with time Calculate inclination between stage III information and CHARM 24h sum on a gage-to-radar (4km information cell) premise Use indicate direct predisposition toward scale (or "conform") organize III information Actual gage values For NSSTC site, inclination variable was 1.36 (radar under-gauge). Precipitation term is spread over more extensive traverse Adjustment produces radar under-gauge

Slide 9

Combined Radar – Rain Gage Product - Summary Individual radar evaluations of precipitation differ incredibly from radar-to-radar without some predisposition modification. The NWS arrange III HDP item which utilizes (a couple of) local rain gages to alter radar evaluations of precipitation for adjustment and Z-R errors demonstrates impressive change in precipitation estimation. Hourly radar precipitation evaluations can be utilized to expand the utility of day by day precipitation estimations (24h aggregates) from gages by applying neighborhood inclination redresses and radar time gauges. Be that as it may, therefore the term of the rain occasion is regularly over evaluated by up to 2 d t (2 hours for this study), 2) the length over gauge will prompt to a tempest power belittle Despite these minor weaknesses, the joined radar and gage precipitation item has an assortment of employments for meso/microscale concentrates on.

Slide 10

Gage OWNERSHIP MAP 80km back JANUARY 2002

Slide 11