W7i7

Note: This post is written primarily for an Indian audience. - - - What leads to a strong or a weak monsoon? What will happen to the monsoon as the world warms? What happens to the monsoon in an El Niño year? -- These are popular and practical questions that the reader has probably heard, read or thought about. This post has no answers for any of these questions, but instead focuses on a more foundational and theoretical question -- What is a monsoon? Easy! Monsoon means the rainy season, right? This first order approximation is generally accepted as universal truth, since it works for a large part of the country. People equate monsoon with rains, especially summer rains. But what about winter rains? They are usually labelled as "post monsoon", and anything else can be put under "pre-monsoon". If you're a bit more nuanced, you may even label some non-summer rains as "non-monsoon". But the general discussion around rains in India tends to revolve around...

I'm a big fan of albedo . I think this concept is very relevant to the climate system, especially to modern climate change. So this is my attempt to familiarize the reader with this concept and show its practical applicability. What is albedo? In simple terms, it is the ability of a surface to reflect sunlight. A surface with high albedo reflects more sunlight, a surface with low albedo reflects less sunlight. Source There are more general terms, such as reflectance, which are used in other sciences. For the sake of climate, we are primarily interested in sunlight. Albedo values lie between 0-1. The overall, average albedo of the Earth is 0.30. This means that 30% of sunlight is reflected back. The rest is absorbed and radiated as heat. Greenhouse gases tend to trap the radiated heat. In the context of a warming planet, it might have been more comfortable if the Earth's albedo was higher. A higher albedo would mean lesser sunlight would be absorbed, lesser heat would be radiate...

हिमाचल प्रदेश से एक के बाद एक भयावह विडीओ और तस्वीरें सामने आ रही हैं। भारी बारिश के कारण कई क्षेत्रों में बाढ़ जैसे हालात हैं। इस संदर्भ में हिमाचल प्रदेश और पूरे देश के नागरिकों से आग्रह है कि वे इन चार ज़रूरी बातों पर गौर करें :   (१) बाढ़ क्षेत्रीकरण में ढील देना आपदाओं को निमंत्रण देने जैसे है अलग अलग विशेषज्ञों द्वारा ये बात बार-बार उठायी जा चुकी है, पर फिर भी नज़र-अन्दाज़ करी जाती है। हर नदी का एक बाढ़-क्षेत्र होता है और उस क्षेत्र में निर्माण करना जोखिम की बात है। प्रशासन के द्वारा बाढ़ क्षेत्र में निर्माण करने की अनुमति देना उचित नहीं है। ये नागरिकों का दायित्व नहीं होना चाहिए, बल्कि ये प्रशासन का दायित्व होना चाहिए की नदियों के बाढ़ क्षेत्र में कोई निर्माण ना हो, ख़ास कर कोई भी सार्वजनिक निर्माण तो क़तई ना हो। बाढ़ क्षेत्रीकरण से कई लोग पहले से वाक़िफ़ होंगे। ये सिर्फ़ पहाड़ी इलाक़ों में ही नहीं, पूरे देश में ज़रूरी ही। इसके बारे में और जानने के लिए ये लेख पढ़ें (अंग्रेज़ी में)। ये ट्वीट भी ज़रूर देखें: भूविज्ञान विशेषज्ञ ने मनाली के एक विडीओ में ढेर होती हुई रोड को...

Greenwashing, greenwashing everywhere, but not a drop of climate relief. Everyone's working on climate change nowadays. Governments are taking climate action, companies are going green, highly capable individuals are innovating, citizens are enthusiastic and engaged. With so much action, what are climate scientists worried about? Surely, we're on track to solving this crisis? This post is written for average Indian citizens. Citizens who are currently facing heatwaves, urban flooding and extreme weather events. Citizens who have noticed that the monsoon is becoming erratic and the weather is becoming unpredictable. Citizens who don't like extreme heat and are wondering when it will all become better, not just for themselves but for their children, their parents and their family.   "When will it get better?" The following graph shows the atmospheric concentration of heat-trapping greenhouse gases (GHGs) with a solid black line. It will continue to get worse as long...

This post is Part III of the series "Climate myths that MUST go". I urge the readers to read the previous posts first, to be able to make sense of this one. ← Myth #1: IPCC = COP ← Myth #2: Climate models are faulty because they are inequitable Myth #3: Climate system metrics = Socio-economic metrics I will admit, this one is trickier to summarize in one neat title line. So if anyone has a suggestion for the line above, they're certainly welcome. But first, let me try to explain what I mean by this strange line. I assume that the reader understands these two facts: (i) Carbon dioxide is a well-mixed gas. Country of emissions do not matter to the climate system. (ii) Carbon dioxide has a long residence time in the atmosphere. After emission, it stays in the atmosphere for a very long time (decades-centuries). These two facts are incontrovertible and unchangeable, discovered by observations of nature. There is no point in "having an issue" or "not agreeing...

This post is Part II of the post "Climate myths that MUST go". To read the previous post, go here: ← Myth #1: IPCC = COP Myth #2: Climate models are faulty because they are inequitable This myth was brought to my attention in the same Twitter conversation as before. The tweet-er wrote: " Also in AR6, the Scenarios assessed by IPCC especially the SSPs perpetuate inequalities going into the future. The IAMs are black boxes and the projections depict a screwed reality of the world by 2100. " They then led me to a podcast by the India Energy Hour , which further led me to an article on Carbon Copy. Before I go any further, I'd like to state that I consider these to be generally good sources for climate articles/information. Thus, to me, the fact that these myths are surfacing on otherwise good platforms is a sign that there is a serious lack of communication between climate scientists and workers in climate justice / policy / communication. The Carbon Copy article b...

For several, several years now, experts have been trying to urge governments and citizens to take action or prepare for the climate crisis. Two things are simultaneously true: that there is some progress, and that there needs to be a lot more progress. In this three-part post, I'd like to identify three myths that throw confusion into the climate conversation, creating hurdles for constructive action. Myth #1: IPCC = COP The IPCC, or Intergovernmental Panel on Climate Change, is a body of experts. Its reports and statements are devoid of political perspectives. One may argue that there is some political influence on what goes into the Summary of Policymakers. That is a valid point, but it is a matter of inclusion/omission of text into the Summary only. The full report is based only on technical findings and political influence can not change facts. COP, or Conference of Parties, on the other hand, is essentially a political body. Delegation from member states (or "Parties...

Earlier this week, Nikki Haley posted an incorrect tweet which led to a lot of outrage among Indians. Unfortunately, this outrage also reveals several myths the Indian climate conversation is rife with. In this post, I use the example of a specific video by the media outlet Firstpost to clarify some misconceptions, and to remind people of some critical climate truths that seem to be getting sidelined by our per capita pride. I request the reader to first watch the video, it is only 5 minutes long. === 00:50 " ..pollution has a time lag. What you emit today, affects us years later. Maybe 10 or 20 years down the line. This is why experts talk about historical pollution. " This is factually incorrect. Pollution -- and more specifically, carbon emissions -- have no such time lag . They affect us immediately . The actual reason why experts talk about historical pollution is the long residence time of carbon dioxide . Once emitted, carbon dioxide can stay in the atmosphere for a ...

Paleoclimate science -- or the science of the climates of the past -- sometimes tells us truly confounding things about how the world was before we arrived on the scene. Here I describe (for the layman) the findings of a study by a group of paleoclimatologists who studied the climate of the Cretaceous Period. This post is based on the paper " Temperate rainforests near the South Pole during peak Cretaceous warmth " by Klages et al. (2020), published in Nature. As the title gives away, the mid-Cretaceous was so warm that there were rainforests near the South Pole! Now if I have your attention, let's explore. Some context The Earth has seen several warm periods in its past. Take a look at how the global temperature is thought to have varied over the last 500 million years. (50 ℉ = 10 ℃. 90 ℉ = 32.2 ℃ . No, I did not choose the scale for the y-axis.) Note where the Cretaceous Hot Greenhouse is marked in the plot below. Klages et al. (2020) focused on the time period betwee...