# Presentation: 744030

## The NYC Urban Dispersion Program (UDP)

***Paul Kalb***
*Presented to *
***The IEEE First Annual Conference on***** ****Long Island Systems, Applications and Technology LISAT2005**
***May 6, 2005****** ***

## Overview	

***Background***
***Description of current capabilities***
***Advanced model capabilities***
***March 05 Field Studies***
***Objectives***
***Meteorology measurements***
***Perfluorocarbon tracers***
***Where we go from here***
***Conclusions/Lessons learned***

***Solution: ******Better computational fluid dynamic models based on micro-meteorological and actual urban canyon conditions.  Need observations to initialize and test!***

***Problem:  ******Current Gaussian Plume models are based on regional weather data - Only provide crude estimates of plume behavior***

**NYC Urban Dispersion Program**

## Current Modeling Capabilities

**Current Modeling Capabilities**

*Seattle Simulation:*
*One-hour snapshots*
*Of plume concentration*
*Size, and direction*

** **

**NYC- Tall buildings Perturb Flow**

- N

- S

- E

- W

## Computational Fluid Dynamic Models

**Computational Fluid Dynamic Models**

## NYC Urban Dispersion Program

***Funded by DHS, DTRA, EPA, and DOE***
***Three field studies: March ‘05, August ‘05, Spring ’06***
***Includes several national labs and academic institutions***
***Working closely with NYC agencies (OEM, NYPD, NYFD,DOMH, DOT, MTA)***
***Student outreach with NY Inst of Tech and Medgar Evers College***

## Advance our understanding and characterization of the effects of urban environments on atmospheric dispersion in large cities leading to improved and validated urban atmospheric dispersion models
Enhance NYC’s emergency capabilities for addressing potential airborne releases of harmful materials
Couple indoor and outdoor studies to further our understanding and characterization of outdoor-indoor exchange

_**Advance our understanding**_** and characterization of the effects of urban environments on atmospheric dispersion in large cities leading to improved and validated urban atmospheric dispersion models**
_**Enhance NYC’s emergency capabilities**_** for addressing potential airborne releases of harmful materials**
_**Couple indoor and outdoor studies**_** to further our understanding and characterization of outdoor-indoor exchange**

** **

**NYC Urban Dispersion Program**
**General Objectives**

## Science Goals for UDP March ‘05

***Understand flow and dispersion in deep urban canyons including rapid vertical transport and dispersion in recirculating eddies adjacent to very tall buildings***
***Carry out tracer experiments with concurrent detailed meteorology to map actual dispersion and aid in development and evaluation of models***
***Conduct concurrent evaluation of personal exposure dose to citizens in the vicinity of release***
***Provide guidance for planning future UDP experiments in NYC***

## Roof top Meteorological  Measurements

## Street-Level Meteorological Measurements

## Model Prediction and Measured Winds

## Perfluorocarbon Tracers (PFTs) 

***Safe to use, odorless, colorless, non-reactive, non-toxic tracer gas – only gram quantities used***
***Can be detected in parts per quadrillion (10******-15******)***
***Medical applications:***
***Used to increase oxygen exchange in pre-mature infants***
***Artificial blood plasma***
***Industrial applications: ConEd and KeySpan use for detecting leaky cables***
***Used extensively by BNL in outdoor and indoor air quality studies***

## 6 separate tracers released at 5 locations
Sampled using:
Programmable stationary samplers (BATS)
Manually changed capillary absorption tubes (CATS) operated by students and EPA personnel
Near-real-time analyzer deployed in a DOE van
Street-level sampling at 21 locations within 200 and 400 m rings
Vertical sampling at 5 heights
Samples brought back to BNL for analysis at Tracer Technology Center

***6 separate tracers released at 5 locations***
***Sampled using:***
***Programmable stationary samplers (BATS)***
***Manually changed capillary absorption tubes (CATS) operated by students and EPA personnel***
***Near-real-time analyzer deployed in a DOE van***
***Street-level sampling at 21 locations within 200 and 400 m rings***
***Vertical sampling at 5 heights***
***Samples brought back to BNL for analysis at Tracer Technology Center***

**PFT Tracer Study****    **

## Location of Stationary PFT Samplers

***Street-level samplers***

***Vertical samplers***

## March ’05 Field Study in Operation

**March ’05 Field Study in Operation**

## UDP in the News...

**UDP in the News...**

## Where We Go From Here...

***Complete data analysis and QA for March ’05 study ***
***Expanded studies in NYC in ’05 and ’06***
***Data evaluation and model verification***
***Installation of permanent meteorological network to assist prediction of plumes under actual conditions***

## Conclusions/Lessons Learned

***Complexities in operating a large field study in NYC cannot be overestimated***
***Requires coordination with city agencies, community groups and local businesses***
***Following organized public affairs strategy led to a very positive reception from the press and public***
***Collaboration among 4 funding agencies was challenging but successful***
***Involvement with students was a win-win***