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Climate model intercomparisons and MIPs

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If you know that future projections about climate change are based on climate modelling, the next obvious question to ask is 一 which climate model(s) are we talking about and trusting to portend our future? The answer lies in CMIP   一 or the Coupled Model Intercomparison Project  一 but before I introduce you to a lot of MIP-like acronyms, some background would be good. Back in 1992, Lawrence Gates wrote about the AMIP   一 or the Atmospheric Model Intercomparison Project. This wasn't a particularly new thing for meteorology, but it was the first of its kind in the field of climatology. Why? Weather and climate models are essentially huge sets of code that take in some input, make a very large number of calculations, and return physically meaningful numbers for things like temperature, precipitation etc. Modelling is an expensive undertaking  一 both in terms of resources and skills. However, short-term weather forecasts tend to take fewer computational resources than long-term cl
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What is a monsoon?

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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
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Albedo, and why you should care about it

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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
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