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Understanding Heavy Rainfall Events in India During El Niño Years

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Introduction When people hear that El Niño is expected to weaken the Indian summer monsoon , they often assume that rainfall will remain uniformly low throughout the season. This is one of the most common misconceptions about the monsoon. Seasonal rainfall and daily rainfall extremes are not the same thing. A season can end with below-normal total rainfall , yet still witness episodes of extremely heavy rainfall over localized regions. Unfortunately, these short-lived but intense rainfall events are often the ones responsible for floods, landslides, urban inundation, and significant loss of life and property.       "El Niño influences the seasonal total rainfall over India, not every individual rainfall event. Therefore, even in an El Niño year with below-normal seasonal rainfall, some regions can still experience episodes of extremely heavy rainfall capable of causing severe floods and landslides." The widespread heavy rainfall observed across India during the past few...

Schools Reopened After Heavy Rainfall: Safety Measures for Safe School Travel

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Introduction After remaining closed for two days due to heavy rainfall, many schools in Pune reopened today. The decision reflected the improving weather situation, with the risk of further heavy rainfall having reduced. Yet, across several parts of the city, the impacts of the previous days' rainfall were still evident. Waterlogged roads, inundated low-lying areas, overflowing drains, damaged road surfaces, and traffic disruptions continued to affect daily life. This situation offers an important reminder: the end of heavy rainfall does not necessarily mean the end of risk. The Rain May Stop, But the Risks Can Persist Weather forecasts help us understand the likelihood of future rainfall, but they cannot instantly remove the impacts of rain that has already fallen. Even after the skies clear, the effects of heavy rainfall often remain for hours or even days. Residual hazards may include: Waterlogged roads concealing potholes or open drains. Flooded underpasses and low-lying street...

बदलती जलवायु में स्वास्थ्य सुरक्षा: पूर्वानुमान से उपचार तक

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 लेख के बारे में यह लेख मूल रूप से ‘संगम’ (अंक 1, वर्ष 2026) पत्रिका में प्रकाशित हुआ था। बदलती जलवायु के कारण स्वास्थ्य पर बढ़ते प्रभाव—जैसे लू, बाढ़, सूखा तथा जलवायु-संवेदनशील रोगों के प्रसार—आज एक महत्वपूर्ण वैश्विक और राष्ट्रीय चुनौती बन चुके हैं। इस लेख में मौसम एवं जलवायु सेवाओं की भूमिका पर प्रकाश डाला गया है, जो समय पर चेतावनी, जोखिम आकलन तथा स्वास्थ्य क्षेत्र की तैयारी को सुदृढ़ बनाकर जन-स्वास्थ्य सुरक्षा में महत्वपूर्ण योगदान देती हैं। यह लेख जलवायु परिवर्तन, स्वास्थ्य और जलवायु सेवाओं के परस्पर संबंध को सरल भाषा में समझाने का प्रयास है। चित्र 1. संगम (अंक 1, वर्ष 2026) पत्रिका का आवरण पृष्ठ, जिसमें "बदलती जलवायु में स्वास्थ्य सुरक्षा: पूर्वानुमान से उपचार तक" लेख मूल रूप से प्रकाशित हुआ था। मूल लेख जलवायु परिवर्तन अब केवल बढ़ते तापमान या पिघलते हिमनदों तक सीमित विषय नहीं रह गया है; यह एक गंभीर जन-स्वास्थ्य चुनौती बन चुका है, जो लोगों के दैनिक जीवन को सीधा प्रभावित कर रहा है। बढ़ता तापमान, वर्षा के बदलते स्वरूप, चरम मौसम घटनाओं की बढ़ती आवृत्ति और बिगड़ती वायु गु...

El Niño, La Niña and the Indian Monsoon: A Climate Story from the Pacific Ocean to India

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Introduction Every few years, changes in ocean temperatures thousands of kilometers away in the tropical Pacific Ocean capture global attention. Terms such as El Niño , La Niña , and even Super El Niño begin appearing in weather and climate forecasts and news headlines. These phenomena are part of the El Niño–Southern Oscillation (ENSO), one of the most important drivers of year-to-year climate variability on Earth. But what do these terms mean, and how can changes in the distant Pacific Ocean influence the Indian monsoon? The answers lie in a fascinating scientific story that connects the Pacific Ocean, the Indian monsoon, and the pioneering work of Sir Gilbert Walker, who sought to unlock the secrets of monsoon prediction while serving in India more than a century ago. What are El Niño and La Niña? El Niño and La Niña are opposite phases of the El Niño–Southern Oscillation (ENSO), a naturally occurring ocean-atmosphere phenomenon in the tropical Pacific Ocean. El Niño El Niño occurs...

How IMD Declares the Monsoon Onset over Kerala and Monitors Its Advance Across India

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Introduction Every year, the arrival of the southwest monsoon is one of the most eagerly awaited weather events in India. Farmers prepare for sowing, reservoirs await replenishment, and millions of people look forward to relief from the intense summer heat. Consequently, considerable attention is paid to the announcement of the monsoon onset over Kerala, which marks the official beginning of the rainy season over the Indian mainland. The onset of the southwest monsoon over Kerala (MOK) is considered the official commencement of the monsoon season over the Indian mainland. It serves as an important meteorological milestone and provides the starting point for monitoring the advance of the monsoon across different regions of the country. The normal date of monsoon onset over Kerala is 1 June , although the actual onset date may vary from year to year depending on prevailing atmospheric and oceanic conditions. Given the widespread interest in the monsoon, many people wonder how the onset o...

What Does IMD's Probabilistic Monsoon Forecast Really Mean?

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Introduction Every year, when the India Meteorological Department (IMD) releases its seasonal monsoon forecast, one common question immediately follows: “So, will the monsoon definitely be good or bad this year?” This year, many students, friends, weather enthusiasts, and members of the public asked similar questions after seeing IMD’s probabilistic monsoon forecast map. At first glance, the map may look confusing because it uses probabilities instead of giving a simple “yes” or “no” answer. However, this probabilistic approach is one of the most scientifically meaningful ways to describe seasonal monsoon forecasts. Unlike a daily weather forecast, which predicts conditions over the next few days, a seasonal monsoon forecast describes the likelihood of different rainfall outcomes several months in advance. Understanding this distinction is the key to interpreting the forecast correctly. Figure 1. Probabilistic forecast of rainfall categories (Below Normal, Normal, and Above Normal) o...