<h2>Overview</h2>
<p>The <span class="key-term" data-definition="Jharia coal fields — a large coal mining region in Jharkhand, India, known for long‑standing underground fires (GS3: Environment/Energy)">Jharia coal fields</span> have been burning beneath the ground for decades. A recent joint study by researchers from the UK and India, including the <span class="key-term" data-definition="CSIR‑Central Institute of Mining and Fuel Research (CIMFR) — a premier Indian research institute under CSIR focusing on mining, fuel and related technologies (GS3: Science & Technology)">CSIR‑Central Institute of Mining and Fuel Research (CIMFR)</span>, reveals that the fire‑affected zones may be hotter and emit more <span class="key-term" data-definition="Greenhouse gases — gases like CO₂ that trap heat in the atmosphere, contributing to global warming (GS3: Environment/Economy)">greenhouse gases</span> than earlier estimates.</p>
<h3>Key Developments</h3>
<ul>
<li>Collapse structures created by burning coal seams can extend vertically over 100 m, acting as chimneys for hot gases.</li>
<li>Field work (2018‑2023) in the Ena, Bastacolla and Tisera collieries documented cavities up to 10 m wide and identified melted rock forms.</li>
<li>Researchers discovered <span class="key-term" data-definition="Paralava — rock that has melted and resolidified due to the high temperature of coal fires (GS3: Geology/Environment)">paralava</span> and a glass‑enveloped rock dubbed “<span class="key-term" data-definition="Birianiite — a newly identified glass‑enveloped rock formed in Jharia’s fire‑collapsed cavities, named for its resemblance to a rice dish (GS3: Geology)">birianiite</span>”.</li>
<li>Computer simulations suggest isolated collapse structures could reach temperatures close to <strong>4,000 °C</strong>, far above typical underground fire estimates.</li>
<li>Using modeled coal consumption, the study estimates a <span class="key-term" data-definition="Global warming potential (GWP) — a measure of how much heat a greenhouse gas traps compared to CO₂ over a specific time horizon (GS3: Environment)">global warming potential</span> of up to <strong>748.72 MT CO₂‑equivalent per year</strong> for Jharia – nearly double India’s total territorial emissions in 2023.</li>
</ul>
<h3>Important Facts</h3>
<p>When mining exposes coal to oxygen, natural oxidation can trigger an <span class="key-term" data-definition="Underground coal fire — a fire that burns beneath the earth’s surface, often ignited when mining exposes coal to oxygen; it releases heat and gases for decades (GS3: Environment/Energy)">underground coal fire</span>. These fires spread irregularly, making direct measurement difficult. The study combined field observations with numerical modelling to overcome this limitation.</p>
<p>The authors note that their temperature and emission estimates exclude certain real‑world processes such as chemical reactions and mechanical deformation, which could modify the results. Mor