Observing Precipitation during NASA
Field Campaigns
Joseph Zagrodnik
First Year Report
University of Washington – Department of Atmospheric Sciences
Advisor: Robert A. Houze
September 22, 2014
NASA OLYMPEX Feasibility Grant NNX12AL54G
NASA launched a new precipitation
measuring satellite on February 27, 2014:
The Global Precipitation Mission (GPM) Satellite
replaces the Tropical Rainfall Measuring Mission
(TRMM) satellite
GPM
TRMM
The GPM polar orbit extends to 65° latitude,
providing full coverage of the mid-latitudes
• The GPM Microwave Imager (GMI) includes two new high-frequency
microwave channels (166 and 183 GHz) that are especially sensitive
to small frozen hydrometers
• The Dual-Frequency Precipitation Radar (DPR) is the first dualfrequency radar in space
NASA Ground Validation (GV) Program
• The Ground Validation program exists to provide ground and
airborne datasets to physically validate the satellite precipitation
algorithms
• The most recent campaigns include:
Iowa Flood Studies
May-June 2013
Integrated Precipitation
Hydrology Experiment
May-June 2014
Olympic Mountains GV
Experiment
Nov 2015 – Jan 2016
Eastern Iowa
Asheville, NC
Seattle, WA
IFloodS Overview
• It snowed at the beginning of May
• A flood occurred!
• Cedar River at Cedar Rapids: 10th highest level in 110 year record
• Turkey River (focus of study) also flooded
• Synoptic setup for flood was similar to record-breaking 2008 flood
Turkey River Watershed
Cause of flooding: 11 MCS passages in 13 days
D
C
04 Z
5/26
A
D
A
18 Z 03 Z
F
I H
A
5/16 5/27
F
B
K
Z
FI C K
A G 20
F
5/19J A J
C G D
E
E
F
J 04 Z H E B I H 00 Z
19 Z 5/25
15 Z 5/21
00
Z
5/29 B
G
G
5/28 5/29
23 Z
K
K K
5/18
H
H
05 Z
5/30
Initiation/Developing
Maximum stratiform coverage
Weakening
*Positions marked every 6 hours, approximate locations based on center of main convective line
*Only systems affecting NE Iowa are considered
Example NPOL image– 0.7° elevation reflectivity
130.4°
RHI
Reflectivity
Differential Reflectivity (ZDR)
Velocity
Specific Differential Phase (KDP)
OLYMPEX Science Objectives
1) Validation of the GPM precipitation algorithms
• Rain vs. snow
• Complex terrain
• Hydrologic applicability
2) Understanding precipitation mechanisms in mid-latitude frontal
systems:
• Transition from ocean/coast to mountainous terrain
• Differences in pre-frontal, frontal, and post-frontal regimes
• Large scale and smaller-scale features
3) Merging numerical modeling and satellite observations to optimize
precipitation estimation
• Achieving these goals requires a comprehensive network of
observations over the coast, interior valleys, and higher elevations
Orographic effects on precipitation in the Olympics
Rain shadow
Ridge top
enhancement
Enhancement
upstream of
topography
( 1000 mm = 39”)
Predominant
synoptic flow
Five year average of Nov-Jan precipitation (model/gauge verification)
Minder et al. (2008)
Frontal
cyclones
crossing a
mountain
range
Easterly
downslope flow
Observed as middle
sector crosses
topography
Broadened by
orographic uplift
Medina et al. (2007)
OLYMPEX Instruments
• Radar
•
•
•
•
•
NASA NPOL (S-band, Dual Pol Radar)
NASA D3R (Ka, Ku band)
Canadian X-Pol (Vancouver Island)
Micro Rain Radar (MRR)
Doppler on Wheels (DOW)
• Aircraft
• NASA DC-8 (Satellite simulators, dropsondes)
• NASA/UND Citation (Microphysics)
• ER-2 (high-altitude)
• Disdrometers
• Up to 20 Parsivels (Rain rate, reflectivity, LWC, drop number/size/concentration)
• 2D-Video
• Precipitation Imaging Probe (PIP)
• Rain gauges
• Pluvio bucket gauges (can melt snow)
• Dual tipping buckets
• Existing network of gauges
Photo credit: NASA PMM
OLYMPEX Trailer
• Deploying to Snoqualmie Pass site in the next few weeks!
Pluvio
rain
gauge
Rainwise weather station
Parsivel
Disdrometer
Pre-OLYMPEX Sites (2014-15)
1,600 m/5,260 ft
50 m/170 ft
920 m/3,010 ft
Grid electricity available
OLYMPEX Proposed Site Locations (2015-16)
1,600
m
95 km
620 m
120 m
90 m
75 km
930 m
70 m
90 m
30 km
660 m
50 m
150 m
80 m
10 m
No electricity
Electricity available
Uninvestigated site
Site elevation (m)
NPOL Radar
D3R Radar
Pictures from IPHEx in rural Rutherford County, NC, June 2014
NPOL View
North
West
East
South
NPOL View—Quinault Basin
Mt. Olympus (NW)
Lake Quinault
Radar beam blockage
Figure from Stacy Brodzik
• Lowest scans have full 360° coverage within 50 km of NPOL
• Cross-sections (RHI) and sector (PPI) scans can be directed up the Quinault Valley
OLYMPEX Timeline
• Fall 2014 – Spring 2015
• Pre-OLYMPEX instrument testing
• Develop real-time website for data dissemination
• Site selection/approvals
• Summer - Autumn 2015
• NPOL site preparation and installation
• Installation of ground instruments, especially at high altitude sites
• November 2015 – January 2016
• OLYMPEX campaign
• Spring - Summer 2016
• Remove ground instruments
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Acknowledgements
• Bob Houze
• Lynn McMurdie
• ATG Staff
• NASA/Wallops Staff
• Grads13
• ATG 626
• Becca + Family
Extra slides
Flooding from Mesoscale Convective Systems
during IFloodS, May 17-31, 2013
Source of flooding: Mesoscale Convective
Systems (MCSs)
• Definition: a cumulonimbus
cloud system that produces a
contiguous precipitation area
~100 km or more in at least
one direction
• Responsible for 65% of
extreme (50-yr) rain events in
US (Schumacher and Johnson 2005)
• Ingredients for flooding:
• Strong low-level jet
• Moisture
advection/convergence
• Slow and/or “training” motion
over a given area (Davis 2001,
Schumacher and Johnson 2005)
Image: UW-Madison CIMSS
2008 vs 2013 Floods
• 2008 (Smith et al. 2013)
• Cedar River at Cedar Rapids nearly
doubled previous flow record over
110 year record
• Estimated damages of $11 billion
• 10 square miles (14%) of Cedar Rapids
was underwater
• 6th largest FEMA disaster declaration
Credit: Matt Herzberger
Downtown Cedar Rapids, 2008
• 2013
• Cedar River at Cedar Rapids: 10th highest crest in 110 years
• Some unnecessary evacuations caused by bad gauge data
Event total rainfall (radar/gauge estimate)
2008
(21 days)
2013
(14 days)
River gauge height: Cedar River at Cedar Rapids
2008
2013
River gauge height: Turkey River at Garber, IA
2008
2013
Synoptic Overview
North American Regional Reanalysis (NARR) dataset
composite averages of the daily mean
May 23-June 13, 2008 vs May 17-31, 2013
500 mb Geopotential Height
2008
2013
Both: Anomalously deep western US trough
2013: weaker height gradient
over central plains, higher
heights over Canada
300 mb wind speed
2008
-Strong southwesterly jet
-Consistent location
2013
-Southwest flow, but jet is
weaker/less consistent
-Result: less organized, but
slower moving systems
925 mb wind speed
2008
2013
-Moist, southerly low-level flow is normal for
May/June, but was anomalously strong
during both of these periods
Initiation and track of MCSs (2008)
01 Z
6/03
F
06 Z
5/29
22 Z
23 Z 20 Z 6/07
5/11 5/26 I
F M D B DLI DBM G J
M H IK B
D 06 Z
G EJ FME
23 Z 6/08 A
E J LK19 Z AC K E
5/29
A
G 6/08
A
L
00 Z
F
00 Z C
H
5/23 21 Z 6/05
H
07 Z
5/26
21 Z
6/05
Initiation/Developing
G
J
F
6/11
Maximum stratiform coverage
Weakening
*Positions marked every 6 hours, approximate locations based on center of main convective line
*Only systems affecting NE Iowa are considered
Initiation and track of MCSs (2013)
D
C
04 Z
5/26
A
D
A
18 Z 03 Z
F
I H
A
5/16 5/27
F
B
K
Z
FI C K
A G 20
F
5/19J A J
C G D
E
E
F
J 04 Z H E B I H 00 Z
19 Z 5/25
15 Z 5/21
00
Z
5/29 B
G
G
5/28 5/29
23 Z
K
K K
5/18
H
H
05 Z
5/30
Initiation/Developing
Maximum stratiform coverage
Weakening
*Positions marked every 6 hours, approximate locations based on center of main convective line
*Only systems affecting NE Iowa are considered
NPOL 0.7° elev. reflectivity—Stratiform Case
135.4°
RHI
Reflectivity
Differential Reflectivity
Velocity
Specific Differential Phase
300 mb jet anomaly
Surface CAPE
OLYMPEX Timeline
• Fall 2014 – Spring 2015
• Pre-OLYMPEX instrument testing
• Develop real-time website for data dissemination
• Site selection/approvals
• Summer - Autumn 2015
• NPOL site preparation and installation
• Installation of ground instruments, especially at high altitude sites
• November 2015 – January 2016
• OLYMPEX campaign
• Spring - Summer 2016
• Remove ground instruments
Daily average rainfall
2008
(21 days)
2013
(14 days)