IMD Investigates Record Temperature Reading at Mungeshpur Weather Station

Context:

The Mungeshpur weather station in Delhi recorded a maximum temperature of 52.9 degrees Celsius, setting an all-time record for any location in India. However, the India Meteorological Department (IMD) later clarified that the record-breaking temperature was likely due to a sensor error or local factor. The IMD is currently investigating the data and sensors to verify the accuracy of the recorded temperature.

Relevance:

GS I: Geography

Dimensions of the Article:

1. Temperature Anomaly in Delhi
2. Why Do Temperatures Vary Within the Same City?
3. Global Temperature Records
4. Temperature Trends in India

Temperature Anomaly in Delhi

Temperature Variation:

• The maximum temperature across Delhi NCR ranged from 45.2°C to 49.1°C in different parts of the city.
  • The IMD operates 20 weather stations in Delhi, 15 of which are automatic weather stations (AWS), including one in Mungeshpur.
  • AWS record and transmit weather data without human intervention.
• Mungeshpur recorded an outlier temperature of 52.9°C compared to other stations.
• The IMD suggested that this anomaly could be due to a sensor error or specific local factors.

Factors Contributing to High Temperatures:

• Rain deficit has contributed to heat accumulation.
• Clear skies and westerly winds from Rajasthan, where temperatures have reached 50°C, have influenced the heat in Delhi-NCR.
• This period typically experiences intense heating across northwest India, including Delhi-NCR.

Predicted Relief from Heatwave:

• The IMD forecasts a reduction in heatwave conditions over the next 2-3 days due to:
  • Gradual temperature decrease associated with an approaching western disturbance.
  • Rainfall and thunderstorms.
  • Southwesterly winds blowing from the Arabian Sea to northwest India.

Why Do Temperatures Vary Within the Same City?

Influence of Weather and Anthropogenic Factors:

• Weather primarily governs the temperature of a region, but human activities significantly impact urban areas like Delhi.

Impact of Urban Infrastructure:

• Concentration of pavements, buildings, roads, and parking lots:
• Hard and dry surfaces offer less shade and moisture, leading to higher temperatures.

Building materials:

• Areas with concrete pavements and buildings experience warmer temperatures.
• Concrete can store nearly 2,000 times more heat than an equivalent volume of air.

Building geometry and spacing:

• Densely populated buildings act as large thermal masses, retaining heat.
• Narrow streets and tall buildings hinder natural wind flows that help cool the area.

Effect of Air Conditioners:

• Heavy use of air conditioners in commercial and residential areas leads to localized higher temperatures as ACs expel significant heat outdoors.

Formation of Urban Heat Islands:

• Factors leading to urban heat islands:
  • Urban areas with fewer trees, vegetation, and water bodies are more likely to become heat islands.
• Natural landscapes help reduce temperatures through shading and the cooling effects of transpiration and evaporation.

Global Temperature Records

Recent Statistics Worldwide:

• In July 2022, the United Kingdom experienced temperatures exceeding 40°C for the first time.
• Last year, a town in northwest China recorded its highest temperature ever at 52°C.
• Sicily, Italy, reached 48.8°C in 2021, marking the highest temperature ever recorded in Europe.
• The highest temperature ever recorded on Earth is 56.7°C in Death Valley, California, USA, in 1913.

Carbon Brief Study Findings:

• A study by Carbon Brief revealed that nearly 40% of the Earth recorded its highest-ever daily temperatures between 2013 and 2023.
• This includes some regions in Antarctica.

Global Warming Trends:

• 2024 was predicted to be extremely warm, following the trend of last year, which was the warmest on record globally.

Temperature Trends in India

Warming in India:

• The rise in temperatures in India is less pronounced compared to global averages.
• Since 1900, annual mean temperatures in India have increased by approximately 0.7°C.
• This is lower than the global average rise of 1.59°C for land temperatures.
• Including ocean temperatures, the current global rise is at least 1.1°C above pre-industrial levels.

Heatwaves in India:

• Despite the lower overall rise in temperatures, heatwaves in India have become significantly more intense.
• In 2023, heatwave conditions were observed as early as February, a winter month typically not associated with heatwaves.

-Source: Indian Express