# Presentation: 531440

## Observations of 2005 Tropical Storm and Hurricane Impact on Louisville Metro PM2.5 Pollution Forecasting

- Observations of 2005 Tropical Storm and Hurricane Impact on Louisville Metro PM2.5 Pollution Forecasting
**AUTHORS:**
- Arthur F. Chang and Cynthia H. Lee
- Louisville Metro Air Pollution Control District (APCD), Louisville, Kentucky, 40204
- Steve Sherman
- Indiana Department for Environmental Management (IDEM), Indianapolis, Indiana, 46204
**ASSIGNED NUMBER:  ****14**

## ABSTRACT:

- Like ozone, PM**2.5 **pollution concentrations are strongly influenced by synoptic meteorological conditions – frontal movements, high and low pressure locations, upper air conditions (ridge and trough formation), etc.  The interaction of meteorology with pollution concentrations is continually examined for the Louisville, Kentucky and southern Indiana area.
- National Weather Service (NWS) weather model’s output variables have been analyzed as ozone predictor variables.  They are: atmospheric transmittance (AT), trend term (1998), relative humidity (RH), daily minimum temperature departure (DEP), wind speed (WS) in mph, and tenths of cloud cover (CC).  An ozone conducive weather pattern is characterized and associated with strong “3-S” conditions – Sunny (low CC), Stagnation (low WS) and Sultry (high temperature and relative humidity).  APCD and IDEM are studying the PM**2.5 **predictor variables for similar trends.
- We have observed that tropical storm conditions alter the formation of ozone and PM**2.5** and require us to use alternative approaches in local forecasting.  The storm systems increase both ozone and PM**2.5 **pollutant concentrations by stalling the frontal movement and increasing stagnation. (see Figures 3, 4 & 6)  Storms can also decrease pollution by increasing the wind speed, cloud cover and precipitation. (see Figures 3 & 7)
- In 2005, the second half of the ozone season was influenced by one of the most active Atlantic hurricane seasons on record.  This provides a unique opportunity to observe the influence of a large number of storms on PM**2.5 **readings and forecasts.

## For particulate matter, we have observed:

- 1.   Tropical systems associated with low PM**2.5**: (see Figures 2, 3 and 7)
- a.   Hurricane Dennis’ (05-13 July) remnant was over the Kentucky-Illinois border from July 11 to July 17 and this   remnant added a total of 53.3 millimeters of precipitation to Metro Louisville.  The remnant of Hurricane Dennis reduced the PM**2.5**** **July monthly average to 19.7 ug/m**3** (See Figure 2) from the 1999-2004 PM**2.5**** **July monthly average of 24.1 ug/m**3**.  The minimum of the 6-year period (1999-2004) of July’s monthly average is 17.8 ug/m**3** in 2004, and the maximum average of 30.4 ug/m**3** in 2002 (see Figure 1).
- b.  Hurricane Katrina (23-31 August) had a Gulf coast landfall and the remnant moved through the Midwest quickly adding 90 millimeters of rainfall to Louisville.  The remnant reduced PM**2.5 **level (see Figures 3
- and 7) with a maximum of 19.2 ug/m**3** (28th August) and a minimum of 7.8 ug/m**3** (30th August).
**Commonly observed features – increased cloud cover and precipitation (see Figure 7)**.
- 2.            2.   2.  Tropical systems associated with high PM**2.5** (see Figures 2, 3, 4, 5 and 6):
- a.   Hurricane Ophelia (06-18 September) increased September 2005’s monthly average to 23.4 ug/m**3**.  The 1999 –2004 PM**2.5**** **September monthly average mean is 17.0 ug/m**3**, with a minimum of 13 ug/m**3** in 2004, and a maximum of 21.7 ug/m**3**** **in 2002. (see Figures 2, 3, 4 and 5)
- b.   Tropical Storm Franklin (21-29 July) gave a maximum daily 24-hr reading of 34.2 ug/m**3** (25 July).
- c.   Tropical Storm Harvey (02-08 August) gave a maximum daily 24-hr reading of 36.6 ug/m**3** (04 August).
- d.   Tropical Storm Irene (04-18 August) gave a maximum daily 24-hr reading of 44.3 ug/m**3** (11 August).
**Commonly observed features – these tropical storm systems had locations near North Carolina and South Carolina’s Atlantic Ocean coastline (see Figure 6).**

## METHODOLOGY

_** **_
_** **_
**1.****                  ****Louisville Metro FRM PM****2.5**** Monthly Average Trends (1999-2005)** **– Figures 1 and 2 **
- Louisville Metro Federal Reference Method (FRM) PM2.5 network has four PM2.5 sites along with one collocated site.  FRM PM2.5 network consists of five R&P 2025 FRM samplers.  Each monthly average was derived from all runs of five samplers from that month in Louisville Metro.  In Figure 1, it displays seven (7) years of monthly averages from 1999 to 2005.  In Figure 2, the month-to-month average comparisons were performed between 2005 and previous six year averages of respective monthly averages (1999-2004).
**2.****                  ****Daily FRM and TEOM PM****2.5**** Time Series Plots (Summer 2005) – Figure 3**
- FRM PM2.5 daily maximum concentrations were derived from five FRM samplers. TEOM (Tapered Element Oscillating Microbalance) PM2.5 daily maximum concentrations were derived from four samplers.  Both daily FRM and TEOM maximum concentrations were plotted for the summer of 2005.
- The tropical storms and hurricanes information were downloaded from National Hurricane Center (NHC).   The locations (A-Atlantic Ocean, G- Gulf of Mexico, and E- end of storm or hurricane) and the remnant of each storm or hurricane after landing (L-Landing) were extracted from the storm tracking tables. The Figure 3 displays storm names and types along with time series plots of both FRM and TEOM for the summer of 2005.
**3.****                  ****Surface Weather Maps** **and** **PM****2.5**** AIRNow Maps – Figures 4, 6 and 7**
- With permission from Unisys Corp., the surface weather maps were downloaded for studying the scope of each stagnation and heavy precipitation.  On the top of Figure 4, three surface weather maps were used to study the effects from Hurricane Ophelia on surface weather conditions by identifying the force winds areas and stagnated locations created by this hurricane.
- At the bottom of Figure 4, three AIRNow PM2.5 maps of same dates were downloaded from AIRNow’s archives for studying a regional PM2.5 episode related to a stagnation condition that was triggered by the Hurricane Ophelia.
**4.****                  ****Tropical Storms/Hurricane Track Information** **– Figures 5 and 6**
- This study uses tropical storm and hurricane tracking data (see Figure 6) from Unisys Corp. (with permission) and National Hurricane Center (NHC).  The force winds profile product (Figure 5) of NHC delineates the wind impact by storms or hurricanes. Figure 5 shows the outer limit of force winds by Hurricane Ophelia on 13th of September 2005.  This experimental product from NHC can potentially be used to identify a stagnated area that is outside the outer boundary of force winds of each storm.

## Figure 1. Louisville Metro Monthly PM 2.5 Averages Historical Trend – 1999-2005

- Figure 1. Louisville Metro Monthly PM **2.5** Averages Historical Trend – 1999-2005

## Figure 2.  Unique FRM PM2.5 Monthly Averages Peak for 2005 - September

**2005 TROPICAL STORMS SEASON IMPACTED ON**

**LOUISVILLE METRO FRM PM**

**2.5**

** ****MONTHLY AVERAGES TRENDS FOR 1999 - 2005**

- 0.0

- 5.0

- 10.0

- 15.0

- 20.0

- 25.0

- 30.0

**MONTH **

**CONC. (ug/m3)**

- 6 yr Avg

- 05 M Avg

- 6 yr Avg

- 14.8

- 14.3

- 13.1

- 12.9

- 16.0

- 19.9

- 24.1

- 22.2

- 17.0

- 15.3

- 15.8

- 15.9

- 05 M Avg

- 12

- 17.1

- 14.3

- 12.9

- 14.9

- 20.5

- 19.7

- 21.1

- 23.4

- 16.4

- 12.7

- 14.8

- 1

- 2

- 3

- 4

- 5

- 6

- 7

- 8

- 9

- 10

- 11

- 12

**DECREASED PM**

**2.5**

**:**

**Hurricane DENNIS**

-  7/5-10/05

- Remnant over

**KY-IL border **

- with rain for

- more than a week.

- --See surface map and PM2.5 daily

- tracking chart for details (see Fig. 3 &4)

**INCREASED PM**

**2.5**

**:**

**Hurricane OPHELIA**

-  9/6-18/05

- stalled on 11th (

**48.9 ug/m**

- 3

- ) over

**Cape **

**Hatteras N. Carolina**

-  & caused long

- stagnation for Louisville.

- --See surface map and PM2.5 daily

- tracking chart for details (see Fig. 3 &4).

- Figure 2.  Unique FRM PM**2.5 **Monthly Averages Peak for 2005 - September

## Figure 3. Time Series Plots of Louisville Metro Daily FRM and TEOM PM 2.5 Summer 2005

- 31-

- Jul

- 2-

- Aug

- 4-

- Aug

- 6-

- Aug

- 8-

- Aug

- 10-

- Aug

- 12-

- Aug

- 14-

- Aug

- 16-

- Aug

- 18-

- Aug

- 20-

- Aug

- 22-

- Aug

- 24-

- Aug

- 26-

- Aug

- 28-

- Aug

- 30-

- Aug

- 1-

- Sep

- 3-

- Sep

- 5-

- Sep

- 7-

- Sep

- 9-

- Sep

- 11-

- Sep

- 13-

- Sep

- 15-

- Sep

- 17-

- Sep

- 19-

- Sep

- 21-

- Sep

- 23-

- Sep

- Day of Month

- PM2.5 Concentration, ug/m3

- Good

- USG

- FRM_Max

- Obs. Midnight-t-M TEOM

**Louisville Metro 2005 Tropic Systems Impacted on PM2.5 FRM and TEOM Data**

**Unhealthy for Sensitive Groups (USG)**

**Moderate **

**Good**

**Fall (9/22/2005)**

**Summer (6/22/2005)**

**H Arlene **

**6/10 -6/12/05**

**H3 Dennis **

**7/05 -7//10**

**Remnant (light **

**color arrow) **

**over KY-lL **

**7/10 -**

**7//17**

**raining daily**

**TS IRENE **

**8/9- 8/15/05**

**H5 KATRINA **

**8/20A-8/25G-28L-31E/05**

**H1 OPHELIA:9/6A-9/14Carolina-17E/05 **

**6/21/05-**

**NO **

**influence by TS**

**TS Franklin **

**               ****7/21 -7//29**

**TS Harvey **

**     ****8/02 -8/08**

**H Nate **

**9/05 -9/10**

- Figure 3. Time Series Plots of Louisville Metro Daily FRM and TEOM PM **2.5** Summer 2005

## Figure 4.  Hurricane Ophelia is Impact on Louisville and

-                 Eastern U.S. by Stagnation and Re-circulation

**Ophelia**

**Ophelia**

**Ophelia**

## Ophelia’s Force Winds09-13-05 2 AM

- Figure 5.

## Figure 6. Tropical Storms located Outside Carolinas’ Coastline Causing Stagnations- Franklin, Harvey and Irene

**08/11/05– 44.3 ****ug/m****3 ****(FRM)**

**08/04/05– 36.6 ****ug/m****3 ****(FRM)**

**7/25/05– 34.2 ug/m****3 ****(FRM)**

**Tropical Storm Franklin**

**TS Franklin**

**Tropical Storm Harvey**

**Tropical Storm Irene**

**TS Harvey**

**TS Irene**

## Figure 7. Remnants of H. Dennis and H. Katrina Caused Cloud Cover and Heavy Precipitation

**   ****07/12/05– 11.9 ****ug/m****3 ****(FRM)**

**08/29/05– 13.1 ug/m****3 ****(FRM)**

**08/30/05–  7.8 ug/m****3 ****(FRM)**

**Remnant Dennis –7/12/05**

**Remnant Katrina – 8/29/05**

**Remnant Katrina - 8/30/05**

## CONCLUSIONS

_** **_
_** **_
- The 2005 record hurricane season provided an unique opportunity to observe and study the strong links between PM**2.5** pollution and tropical storm low-pressure surface systems.  This study observed that the location of large low-pressure surface systems provide two different predictor variables, **stagnation** (see Figures 4, 5 and 6) and **heavy precipitation** (see
- Figure 7), for forecasting PM**2.5** pollution.
**Stagnation** – increases PM**2.5** forecasted concentration.  We have observed that the Atlantic tropical storm systems that were located in the Atlantic Ocean near North Carolina and South Carolina’s coastline triggered large regional PM**2.5** episodes in the Louisville Metro area by increasing the stagnation and in some cases the re-circulation of polluted air masses.  They were Hurricane Ophelia (see Figure 4), Tropical Storm Franklin, Tropical Storm Harvey and Tropical Storm Irene (see Figures 3, 4, 5 and 6).
- By animating the U.S. surface weather maps, one can illustrate large areas of stagnation by observing the stalling of the frontal weather systems (see Figures 4 and 6). One of the best episodic examples for Louisville PM**2.5** forecasting study in 2005 hurricane season was Hurricane Ophelia. The stagnation lasted for six days (from September 9**th** to September 14**th**). This stagnation provided a PM**2.5** conducive condition for many states in the two third of eastern country and major cities including the Louisville Metro area.  Surface weather map observations (see Figures 4 and 5) provided an explanation - **STAGNATION**.

## Heavy Precipitation - decreases PM2.5 forecasted concentration.  Both remnants of Hurricane Dennis and Hurricane Katrina generated heavy precipitation for the Louisville Metro area.  Time series plots (see Figure 3) of Louisville FRM and TEOM PM2.5 daily concentrations showed a substantial decrease of PM2.5 concentrations due to constantly washing out high PM2.5 concentration air masses during the passes of both remnants (see Figure 7).  

- The variables of heavy precipitation from Hurricane Dennis (see Figure 4) and stagnation from Hurricane Ophelia (see Figure 4) were dominating enough that they altered Louisville’s monthly PM**2.5** average historical trend. Instead of peaking in either July or August from previous years, monthly averages in 2005 peaked in September (see Figures 1 and 2).
- Both stagnation and heavy precipitation predictor variables can be used to quantitatively develop Louisville’s local numerical PM**2.5 **forecasting formulation and model in future PM**2.5 **forecasting.  National Weather Service (NWS) local weather models outputs (wind speed, precipitation, and others) and National Hurricane Center products (force winds profile (see Figure 5), position estimates (see Figure 6), and others) generate daily predictor variables that can be use to qualitatively and quantitatively forecast local and regional PM**2.5 **episodes.

## Credits

- UNISYS Corp.
- National Hurricane Center
- National Weather Services - Louisville
- AIRNow
- Dr. W. Geoffrey Cobourn, Mechanical Engineering Department, University of Louisville

## References:

** **
- 1.      Hubbard, M.C.; Cobourn, W.C.    Development of a Regression Model to Forecast Ground-Level Ozone Concentration in
- Louisville, KY;  *Atmos. Environ*. **1998**, 32, 2637-2647.
- 2.      Cobourn, W.G.; Hubbard, M.C.   An Enhanced Ozone Forecasting Model Using Air Mass Trajectory Analysis;  *Atmos. Environ.*  **1999**, 33, 4663-4674.
- 3.      Cox, W.M.; Chu, S.   Meteorologically Adjusted Ozone Trends in Urban Areas:  A Probabilistic Approach;  *Atmos. Environ.  Part B.  Urban Atmos.*  **1993**, 27, 425-434.
- 4.      Bloomfiedl, P.;  Royle, J.A.;  Steinberg, L.J.;  Yang, Q.   Accounting for Meteorological Effects in Measuring Urban Ozone Levels and Trends;  *Atmos. Environ.*  **1996**, 30, 3067-3077.
- 5.      Tropical Storms and Hurricanes Data; Available at National Hurricane Center:**  **_[http://www.](http://www.nhc.noaa.gov/archive/2005/index.shtml)__[nhc](http://www.nhc.noaa.gov/archive/2005/index.shtml)__[.noaa.gov/archive/2005/index.](http://www.nhc.noaa.gov/archive/2005/index.shtml)__[shtml](http://www.nhc.noaa.gov/archive/2005/index.shtml)_ (accessed 2005 and 2006)
- 6.      PM 2.5 2003 – 2005 Mapping Data; Available at EPA AIRNow: _[http://www.airnow.gov/](http://www.airnow.gov/)_
- (accessed 2005 and 2006)
- 7.      U.S. Surface Weather Mapping Data; Available at UNISYS Corp: _[http://weather.](http://weather.unisys.com/surface)__[unisys](http://weather.unisys.com/surface)__[.com/surface](http://weather.unisys.com/surface)_ (accessed 2005 and 2006)
- 8.      Louisville Local Weather Data; Available at Louisville National Weather Service (NWS):
- 		_[http://www.](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)__[srh](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)__[.noaa.gov/data/forecasts/OHZ032.](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)__[php](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)__[?](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)__[warncounty](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)__[=OHC151&city=Louisville](http://www.srh.noaa.gov/data/forecasts/OHZ032.php?warncounty=OHC151&city=Louisville)_
- 		(accessed 2005 and 2006)