Extreme Value Analysis of Environmental Time Series: An Application to Trend Detection in Ground-Level Ozone: Comment: Are Ozone Exceedance Rates Decreasing?

ARE OZONE EXCEEDANCE RATES DECREASING? COMMENT ON "EXTREME VALUE ANALYSIS OF ENVIRONwlENTAL TIME-SERIES: AN APPLICATION TO TREND DETECTION IN GROUND-LEVEL OZONE" BY

R.L. Smith (1989) in his Statistical Science discussion paper, proposed new methods fora.Ilalyzingextreme values based on the point process view of highlevelexceedances,andillustratedthem with a detailed analysis·of ozone data frqm Houston, Texas. The methods are powerful and, in particular, the point process ofcluster peaks over a high threshold provides a remarkable condensation of the massiv...

Extreme Value Analysis for Evaluating Ozone

Tropospheric ozone is one of six criteria pollutants regulated by the US EPA, and has been linked to respiratory and cardiovascular endpoints and adverse effects on vegetation and ecosystems. Regional photochemical models have been developed to study the impacts of emission reductions on ozone levels. The standard approach is to run the deterministic model under new emission levels and attribut...

Stratospheric ozone time series analysis

Time-series Analysis of Ground-level Ozone in Muda Irrigation Scheme Area (mada), Kedah

It has long been recognised that pollutant gases cause significant impacts on crops and studies conducted revealed that ground-level ozone is responsible for most of the crop-yield losses from air pollutants whereby losses from other pollutants are minimal, relative to ozone (Fuhrer et al., 1997; Pleijel et al., 1998; Ishii et al, 2004). Ozone is a secondary pollutant resulting from photochemic...

Detection of Changes in Ground-Level Ozone Concentrations via Entropy

Ground-level ozone concentration is a key indicator of air quality. There may exist sudden changes in ozone concentration data over a long time horizon, which may be caused by the implementation of government regulations and policies, such as establishing exhaust emission limits for on-road vehicles. To monitor and assess the efficacy of these policies, we propose a methodology for detecting ch...