ABSTRACT

The study was conducted in 2019 to investigate the greenhouse gases (GHGs) concentrations in rural as well
as coastal Patharghata upazila of Bangladesh. This study received equipment supports from Khulna
University of Enginnering & Technology, Khulna. Air quality was monitored using Gas Analyzers (model:
Handheld 3016) from various locations in Patharghata Upazila. Reading continued for 30 minutes (minimum
time). The wind direction of those sites was also monitored. Finally, the analyzed data was combined,
presented as a table and included in the manuscript. Five individual GHGs (CO, NOX, SOX, PM10 and PM2.5)
were measured in this study. CO concentrations were measured at four selected locations and the
concentrations lied within in the 1.0-1.4 mg/m3
range. The measured NOX concentration (122 µg/m3)
exceeded the standard value (100 µg/m3), hence there is the possibility of health risk. The AQI for SOX can
be placed in good/green state. In case of PM (PM10 and PM2.5) the concentrations exceeded the international
standards (WHO and US) but were within the limit set for Bangladesh.
Keywords: Greenhouse gases, emission, rural area, coastal district, Pathatghata upazila.

Introduction

Greenhouse gases (sometimes abbreviated as GHGs) are gases that absorb and emit radiant energy in the
thermal infrared range. Greenhouse gases cause the greenhouse effect (IPCC, 2015). The major greenhouse
gases in the Earth’s atmosphere are water vapor (H2O), carbon dioxide (CO2), methane (CH4), nitrous oxide
(N2O), and ozone (O3). In the absence of greenhouse gases, the average temperature on the Earth’s surface
will be about -18°C (NASA GISS, 2016) instead of the current average of 15°C (Karl and Trenberth, 2003;
NASA, 2010). Global warming can cause the Earth’s surface temperature to exceed historical values by
2047, adversely affecting ecosystems, biodiversity, and human life. Current emissions rates can raise
temperatures by as much as 2°C, which the UN IPCC has specified by 2036 as an upper limit to avoid
“dangerous” levels (Mora, 2013).
Human activity since the beginning of the Industrial Revolution (in1750) has increased the atmospheric
concentration of carbon dioxide by 45% from 280 ppm in 1750 to 415 ppm in 2019. This increase occurred
despite the absorption of more than half of the emissions from various natural “sinks” involved in the
carbon cycle (ESRL, 2008). The majority of anthropogenic carbon dioxide emissions are mainly from the
burning of fossil fuels of coal, oil and natural gas, including deforestation, land-use change, soil erosion,
and agriculture (IPCC, 2015). The major source of anthropogenic methane emissions is animal agriculture,
followed by temporary emissions from gas, oil, coal and other industries, solid waste, waste water and rice
production. However, the contribution of each gas to the greenhouse effect is determined by its properties,
its quantity, and the indirect effects it causes. Schmidt et al. (2010) analyzed how individual components of
the atmosphere contribute to the overall greenhouse effect. They estimated that water vapor accounts for
about 50% of the Earth’s greenhouse effect, 25% for clouds, 20% for carbon dioxide, and 5% for traces of
greenhouse gases and aerosols. The direct radiative effect of the mass of methane is about 84 times stronger
than the same mass of carbon dioxide over the 20-year timeframe, but it is present in much smaller
concentrations so that its total direct radiative effect has so far been smaller, in part due to its shorter
atmospheric lifetime in the absence of additional carbon sequestration. On the other hand, methane has a
large indirect radiation effect because it contributes to the formation of ozone in addition to the direct
radiation effect. Sindel et al. (2005) stated that the contribution of methane to climate change is at least