An investigation of the relationship between surface temperature and total ozone over New Delhi, India, using a frequency domain technique and binary fuzzy relation

ABSTRACT

This work has explored spectral analysis to view the relationship between the time series of surface temperature and total ozone concentration (TOC) over New Delhi from 1995 to 2005. The time series has a discernible spectral density when analysed using harmonic analysis. Between the surface temperature and TOC, a common cycle of period of 10 months has been noted for the years under investigation. In addition, a binary fuzzy relation method has been used to examine the relationship between surface temperature and TOC using membership matrices produced by max-min composition. Overall, a fuzzy set theoretic approach has established a connectivity between surface temperature and TOC, and a spectral analysis approach which falls under the category of frequency domain approach has established the existence of a common cycle between these two time series.

KEYWORDS:

• Fuzzy set
• total column ozone
• surface temperature
• spectral analysis
• binary fuzzy relation

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The Surface Temperature data utilized in the work are taken from the Indian Institute of Tropical Meteorology website (IITM). https://tropmet.res.in/static_pages.php?page_id=52#data is the link to the data. And Total ozone (TO) data are collected from the website https://woudc.org/data/explore.php#.