<p>When rain displaces pore gasses in the soil, bubbles of soil gas are released into the atmosphere. It's impossible to be precise about the composition because it is so variable from place to place. It varies according to soil type, organic content, degree of rotting, temperature, and the microbiological cross section (itself hugely variable). Most soil gas is odourless, such as nitrogen, carbon dioxide, methane, etc. Others, like geosmin, are very smelly. In addition  to 'petrichor' there are terpenes, aldehydes, alcohols and esters, to name but a few of the natural volatile organic compounds.
Of course, one cannot rule out the foul smell or rotting animals in some places.</p>

CC BY-SA 3.0
2016-05-13T15:51:23.763Z
2016-05-13T15:51:23.763Z
Gordon Stanger
<p>Last day we had first rain after 3-4 months of hot&amp;dry weather, and within 3-4 minutes a rotting smell came from nowhere. Due this smell I had running nose for a day. What might be the reason for this bad smell? Did anyone heard of this kind of problem? (or is this just some local issue related to sewage, or some animal dead body which was dry came in contact with water)</p>

<p>I am not referring to <a href="https://en.wikipedia.org/wiki/Petrichor" rel="nofollow">Petrichor</a>, which is fresh earthly smell.
And I am in India.</p>

<hr>

<p><em>I hope this is on-topic here</em></p>

CC BY-SA 3.0
2016-05-12T20:51:25.863Z
Could be acid rain.
stali
<temperature><rainfall><earth-system><rain>
Reason for rotting smell after first rain of the season?
JAVY
# Reason for rotting smell after first rain of the season?

(Asked by: username_0 on 2016-05-12)

Last day we had first rain after 3-4 months of hot&dry weather, and within 3-4 minutes a rotting smell came from nowhere. Due this smell I had running nose for a day. What might be the reason for this bad smell? Did anyone heard of this kind of problem? (or is this just some local issue related to sewage, or some animal dead body which was dry came in contact with water)

I am not referring to [Petrichor](https://en.wikipedia.org/wiki/Petrichor), which is fresh earthly smell.
And I am in India.

---

*I hope this is on-topic here*

**Tags:** temperature, rainfall, earth-system, rain

> **Comments:**
> **username_1**: Could be acid rain.  

---

## 1 answers

### Answer by username_2 on 2016-05-13. Score: 3

When rain displaces pore gasses in the soil, bubbles of soil gas are released into the atmosphere. It's impossible to be precise about the composition because it is so variable from place to place. It varies according to soil type, organic content, degree of rotting, temperature, and the microbiological cross section (itself hugely variable). Most soil gas is odourless, such as nitrogen, carbon dioxide, methane, etc. Others, like geosmin, are very smelly. In addition to 'petrichor' there are terpenes, aldehydes, alcohols and esters, to name but a few of the natural volatile organic compounds.
Of course, one cannot rule out the foul smell or rotting animals in some places.


---

