new activities to expand the caribbean sounding and surface networks the iasclip and coconet...
TRANSCRIPT
New activities to expand the Caribbean sounding
and surface networks
The IASCLIP and COCONet initiatives
National Severe Storms Laboratory/NOAA
Norman, Oklahoma
Two distinct activities with overlapping interests in the Caribbean region
• IASCLIP - Intra-Americas Study of Climate Processes (NOAA initiated effort to improve climate prediction over the region between North and South America)
and...
• COCONet - Continuously Operating Caribbean GPS Observational Network (NSF Funding, implemented by UNAVCO, which is “a non-profit membership-governed consortium, facilitates geoscience research and education using geodesy.”
Science questions related to COCONet
COCONet principal objective is to measure crustal motion
Source: COCONet proposal
Source: UNAVCO
Typical GPS site
Bedrock (ideally)
Source: UNAVCO
Precipitable Water and Slant Water
• SW can be estimated along single GPS ray paths
• Simultaneous observations along 10-12 ray paths
• PW is essentially an average of SW (after they have been
scaled to zenith)
(From Braun and Rockin 2001 AMS)
Precipitable Water and Slant Water
Suominet real-time displays provide the PW and output from the surface station, among other things...
PW value is 1) high time resolution and 2) absolute accuracy to compare with other measurements
(From Vaisala VXT520 users manual)
Used for GPS-MET Temp and Pressure data
Not ideal for wind measurementsbut inexpensive ~$2K
COCONET OVERLAPS IASCLIP TO CERTAIN DEGREE
Mexico GPS network also being planned...~100 sites
Fig courtesy PEnglehart/ADouglas
May-Oct PW climo (mm)
PW values don’t explain precip variability at small spatial scales
Where GPS PW really helps - detecting biases in radiosonde data and Providing long-term trends that are believable - Reanalysis validation
Suspicious!Suspicious!
Possible radiosonde networkwith adaptive (white) sites
(was part of JHT proposal this year)COCONet sites close to all RAOB sites
IASCLIP = Intra Americas Study of Climate Processes
A CLIVAR-VAMOS Monsoons Program (FY09 - FY14)
Possible radiosonde networkwith adaptive (white) sites
(was part of JHT proposal this year)
IASCLIPWeb site...
IAS centerpiece: Western Hemisphere Warm Pool (WHWP)
2000
Small WHWP
Fewer tropical storms
2005
Large WHWP
More tropical storms
IASCLIP: Predicting IAS summer climateEmphasis on extreme events
1. Identifying and Quantifying Sources of Predictability
(WHWP, Local vs. Remote Influences, Land-Atmosphere Interactions, NASH, LLJ, Orography …)
2. Climate foci: TC activity, dry summers, Midwest floods, early/late rainy season onset, Mid-summer drought anomaly
3. Multi-Space and Time scale Issues:
WHWP scale — How SST is forced by large scale phenomena (ENSO, NAO, Amazon); how WHWP affects moisture flows, vertical shear, CAPE
Mesoscale — diurnal heating and orography modify large scale regime over islands & Central America
Sfc in-situ (small islands) — rain gauges, solar radiation & wind to provide ground truth for large scale models and verify/improve satellite products over ocean areas.
Sfc in-situ (large islands, isthmus) — provide data for understanding scale interactions and for downscaling. (This is where people live, so forecasts are critical in these areas.)
Soundings: evaluate need and feasibility of regular observations in priority areas, perhaps adaptively.
Add thermistor chains to NDBC buoys — 3D development of warm pool & heat budget.
Can be real-time for climate monitoring (CPC, NCDC) and hurricane forecasting (NCEP, NHC, also some NWS local offices).
Could be fine-tuned as needed to satisfy changing needs of research community.
An IASCLIP monitoring effort should evolve into a sustainable climate observing system for the region.
Advantages of monitoring efforts
Caribbean soundings are historically unreliable(compare with San Juan at bottom) - CHUAS needs reworking
Lack of GPS-reported T(z) profiles in the IAS (1999-2005)
What is lacking in ocean measurements?
Failed Nov-22-2009
Failed Jan 13 2011
Buoys costly to maintain, slow to fix...
Small islands in Caribbean region- a unique opportunityfor establishing low cost surface and raob sites
Colombian and Jamaican islands...with facilities and logistical arrangements
Jamaican cays
Serranilla
Pedro Cay, Jamaica
Inexpensive radiosonde systems can be used for adaptive tropical soundings, simplifying logistics and reducing annual costs.
IASCLIP may apply this concept for higher spatial density measurements at lower temporal resolution. Same procedure can be applied to measuring hurricane environment .
Possible radiosonde networkwith adaptive (white) sites
(was part of JHT proposal this year)
Adaptive obs’s ~$75K / summer
Possible surface met sites in western Caribbean (some overlap possible between IASCLIP and COCONet)
Current NOAA Met buoys in red - may add thermistor chains for IASCLIP
Why are all these observations important?
• Allow for more effective use of hurricane aircraft resources
• Better specification of climate and its long-term variability
Summary
1. GPS-Met sites going into Caribbean region starting this year (10) and next year (40). Substantial Mexican GPS-Met network likely - timeline and details unclear at the moment.
2. IASCLIP observational component should be a mix of mostly climate-oriented measurements, though some have potential for real-time hurricane analysis/forecasting. Funding of IASCLIP uncertain.
3. The above are likely to provide an improved envelope of observations for hurricane-focused measurements for research and forecasting.