Urban Dispersion Program New York City Mesonet ROOFTOP WEATHER STATION NETWORK

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1 Urban Dispersion Program New York City Mesonet ROOFTOP WEATHER STATION NETWORK GENERAL DESCRIPTION Introduction The Department of Homeland Security has established a meteorological research program in New York City. The Urban Dispersion Program is described fully on the web site A part of the UDP is the installation of a network of meteorological instruments across New York and beyond into neighboring regions in New Jersey and Connecticut. The Brookhaven National Laboratory is taking a lead role in setting up the network, referred to as the NYC mesonet. The NYC mesonet is being developed in collaboration with, on a national scale, the Department of Homeland Security, Department of Defense, Department of Energy, and the Environmental Protection Agency, and, on a local scale, with support from the NYC Office of Emergency Management. The OEM is coordinating the program with the the police, fire department, and other city agencies. In plain terms, the NYC mesonet will provide critical meteorological measurements in real time for use during emergency situations whether acts of God or intentional. Measurements will be transmitted instantly to data collection centers where they will be disseminated to emergency managers and to a variety of computer modeling centers. The computer models will predict dispersion of airborne contaminants and make these available to the emergency management activity. The NYC mesonet must provide data of the winds, inversions, fronts, seabreezes, and heat effects from the street level (in the urban canyons ) to well above the tops of the tallest buildings. To accomplish this task many different instruments must be used. This document describes an array of rooftop meteorological weather stations. The rooftop array forms the core of all other mesoscale measurements. The rooftop measurements will be placed on particular, carefully selected buildings. We seek buildings that are by themselves and very tall so that the winds over the building are not affected by turbulence from nearby structures. The location of the buildings is important as we seek to provide good coverage of the greater NYC megacity. In this document we will review the building selections, the meteorological hardware, and the communication scheme. TABLE OF CONTENTS Coverage 2 Weather Instruments 3 Free-standing Tower 4 Communication 5 Installation & Maintenance 6 NYCCT Station 7 Contact: Michael Reynolds Brookhaven National Laboratory Brookhaven National Laboratory Page 1 of 7

2 THE NYC MESONET AND THE MIDTOWN EXPERIMENT Currently, in 2005, we plan to deploy six rooftop stations in the general area of midtown Manhattan. Five of the selected sites are shown in the figure below. These were selected to provide good coverage of the Manhattan midtown area, where a set of experiments will be conducted this summer. The mesonet also includes certain weather stations that are operated by or on collaborating institutions. On the map, stations marked in blue are currently operating and are being collected in the NYC mesonet. The stations marked in red are planned to come on line by July For the summer experiment, a small and a large triangle of observations has been defined as shown. The stations SIT and CCNY are weather stations operating on Stevens Institute of Technology and City College of New York. These stations were funded and deployed at the expense of the supporting institutions but with consultation with BNL. The station marked NYCCT is planned by the CUNY New York City College of Technology. The NYCCT site is ideally placed south of the city and in a position to provide an early indication of the summer seabreeze as it sweeps in from the ocean. A map showing the locations of five NYC mesonet rooftop weather stations that are planned in 2005 for the Manhattan area. The station at NYCCT is being funded and deployed by the school with support from BNL. Brookhaven National Laboratory Page 2 of 7

3 THE NYC MESONET INSTRUMENTATION The rooftop weather stations were designed by a team of urban research scientists. The final suite of instruments are considered to be the best possible and of climate research quality. A block diagram of the system is shown below. A block diagram of the rooftop meteorological station for the NYC mesonet. This configuration has UHF radio communication. Other systems can make use of wireless internet and wireless mesh technologies. R.M. YOUNG WIND MONITOR MARINE VERSION ANALOG/DIGITAL VAISALA WEATHER STATION WXT-501 S,D,T,RH,P,PPT EIA485 UHF TRANSMITTER TELEDESIGN TSI B ANALOG VAISALA T/RH HMP-45A ASPIRATOR METONE MODEL 076B-7308 ZENO-3200 SW VERSION: 2.17 with GSI DIGITAL EIA485 OTHER INSTRUMENTS The rooftop meteorological station is deployed on a 6-m high free-standing tower.the freestanding tower is installed in a short time by two. System Enclosure Brookhaven National Laboratory Page 3 of 7

4 DETAIL E SCALE (FEET) DETAIL C 20' 6' 6' DETAIL A DETAIL B DETAIL D The six-meter meteorological tower is designed to be free standing with distributed weight. The design has been approved by a professional engineer to withstand wind speeds in excess of 140 mph (beyong NYC regulations). Each foot holds three 30 lb concrete blocks (total weight less than 500 lbs). Two different wind sensors will be used in the NYC mesonet wind station: the Vaisala WXT510 weather transmitter and the RM Young Wind Monitor. The WXT510 is a complete weather station with two-dimensional sonic anemometer, temperature and relative humidity, barometer, and rain gauge. The wind monitor is a established standard in meteorological measurements. Brookhaven National Laboratory Page 4 of 7

5 NYC MESONET COMMUNICATION The data are collected in the data logger each three seconds and from those, an average data string is transmitted each minute. The one-minute data must be relayed to the BNL data center within a few seconds of availability. two methods are currently used for the data transmission, internet, and UHF radio. The UDP mesonet stations are equiped with special UHF transmitters and send their one-minute data lines to a central relay site on Rockefeller Center (RFC). The RFC site receives all transmissions froom any available reporting stations andforwards them directly over the 58 miles to the BNL meteorological tower in Upton Long Island. The BNL radio network is an approved frequency to operate at 100 Watts of power. The data are transmitted at very high rates and the electronic transceivers are highly efficient. Thus solar panels are sufficient to handle hundreds of reporting stations. View from Rockefeller Center towards BNL in Upton Long Island. The small Yagi antenna provides sufficient gain to reach the BNL meteorological tower. There are other instances where it is better to use internet connections. Where internet is reliable and available, and if the radio link is not possible, the internet provides a reasonable alternate route. Most of our external sites, including CCNY and SIT are available through internet connections. The new station at NYCCT will use its internet link at first, but plans are to bring in this important station onto the UHF network as soon as funds are available. Brookhaven National Laboratory Page 5 of 7

6 NYC MESONET INSTALLATION AND MAINTENANCE DEPLOYMENT The system is moved to the rooftop in pieces and deployed in approximately one hour. Some time is required to align the antenna and to confirm the radio connections are strong. MAINTENANCE System failures can occur at any time. It is expected that failures will occur in the first three months of the deployment (infant mortality) but after the initial trial period a mean time between failure (MTBF) of more than two years is expected. Thus we expect fewer than one failure, requiring an engineering visit per year. We will plan to visit the station twice per year for regular maintenance and calibration activity. These will be scheduled visits and will be coordinated with building managers. A 6-m tower on One Penn Plaza. Brookhaven National Laboratory Page 6 of 7

7 NYC MESONET NYCCT STATION The station located at 330 Jay Street is being developed by a joint collaboration between BNL and NYCCT. The college is procuring all instrumentation and will provide the internet connections for the data collection at BNL. In order to save expenses during this first round of funding, an internet connection makes a good alternative. At the same time, the data would be available to students and could be used as a learning tool. Y R 330 JAY The wireless internet path from the rooftop tower via a repeater on the roof edge and down to the NYCCT internet. The Y boxes will be set up in a secure tunnel mode which eliminates any unauthorized use. Y NYCCT REQUESTS TO HOST BUILDING The weather station is designed to require a minimal amount of support from the host building. In this installation the following are requested: 1. Power connection. We can provide high quality outdoor utility cable to an available 120 VAC standard power outlet. 2. Access to the roof of the utility room. During the site visit we selected the roof of this room as the best possible exposure and the least contaminated by local structure. TIMETABLE Deployment of the station will take place over a two day period. The first day we will install the station and on the second day we will install the wireless internet connection. It is possible the entire installation can take place in one day. The exact date of the installation depends on equipment procurements. We expect to be ready to deploy during July The views from the top of 330 Jay St. show the excellent exposure from this site. NYCCT CONTACT: Reggie Blake Professor NYC College of Technology (718) rblake@citytech.cuny.edu Brookhaven National Laboratory Page 7 of 7