Tag: habitability

Some comments on India’s heat

On May 5, a couple people from BBC World reached out to me, presumably after reading my piece last week on the heatwave in North India and the wet-bulb temperature, for a few comments on a story they were producing on the topic. They had five questions between them; I’m reproducing my answers roughly verbatim (since I spoke to them on phone) below.

Are these high temperatures usual?

A: Yes and no. Yes because while these numbers are high, we’ve been hearing about them for a decade or so now – and reading about them in news reports and hearing anecdotal reports. This isn’t the first such heatwave to hit India. A few years ago, peak summer temperature in Delhi touched 47º C or so and there were photos in the media of the asphalt on the road having melted. That was worse – that hasn’t happened this time, yet. That’s the ‘yes’ part. The ‘no’ part has to do with the fact that India is a large country and some parts of the country that are becoming hotter are probably also reaching these temperatures for the first time. E.g. Bangalore, where I live, is currently daily highs of around 35º C. This is par for the course in Chennai and Delhi but it’s quite hot for Bangalore. This said, the high heat is starting sooner, on this occasion from mid-March or so itself, and lasting for longer. That has changed our experience of the heat and our exposure. Of course, my answers are limited to urban India, especially to major cities. I don’t know off the top of my head what the situation in other parts is like.

The government has said India has a national heat plan and some cities have adopted heat action plans. Are they effective?

Hard to say. Only two score or so cities have adopted functional heat action plans plus they’re cities, which is not where most of India lives. Sure, the heat is probably worse in the urban centres because of the heat island effect, but things are quite poor in rural areas as well, especially in the north. The heat also isn’t just heat – people experience its effects more keenly if they don’t have continuous power supply or access to running water, which is often the case in many parts of rural India. The benefits of these action plans accrue to those who are better off, typically those who are upper class and upper caste, which is hardly the point. When North India’s heatwave was underway last week, NDTV interviewed shopkeepers and small scale traders, vendors, etc. about whether they could take time off. All of them without exception said ‘no’. Come rain or shine, they need to work. I remember there being vicious cyclones in Chennai and waking up in the morning to find the roads flooded, trees fallen down and loose electric wires – and the local mobile vegetable vendor doing his rounds. Also, in urban areas, do the heat action plans account for the plights of homeless people and beggars, and people living in slums, where – even if they’re indoors – they have poor circulation and often erratic water and power supply?

What should the government do?

That’s a very broad question. Simply speaking, the government should give people who can’t afford to shut their businesses or take time off from work the money they’d lose if they did, and rations. This is going to be very difficult but this is what should be done. But this won’t happen. Even during the COVID-19 pandemic, the Indian government didn’t plan for the tens of thousands of migrant labourers and daily-wage earners in cities, who, once the lockdown came into effect, slowly migrated back to their home towns and villagers in search of livelihoods. This sector remains invisible to the government.

[I also wanted to say but didn’t have the time:] the experience of heat is also mediated by gender, geography and caste forces, so state interventions should also be mediated by them. For example, women in particular, in rural India and especially in Central and North India (where literacy is relatively lower) operate in settings where they have few rights and little if any financial and social independence. They can seldom buy or own land and go out to work, and often labour indoors, performing domestic tasks in poorly ventilated residential spaces, venture out to fetch water from often distant sources – a task performed almost exclusively by women and girls –, often have to defecate in the open but do so early in the day or late in the evening to avoid harrassment and shame, which then means they may not drink water to avoid peeing during the day but which would render them vulnerable to heat stress, etc. If state interventions don’t bend around these realities, they will be useless.

The moment you mention data or figures that you say you obtained from this government, the first thought that comes to mind is that it’s probably inaccurate, and likely an underestimate. Even now, the Indian government has an ongoing dispute with the WHO over the number of people who died during the pandemic in India: India is saying half a million but the WHO as well as many independent experts have said it’s probably 3-5 million. For example, if the government is collecting data of heat-related illnesses at the institutional level (from hospitals, clinics, etc.) you immediately have a bias in terms of which people are able to or intend to access healthcare when they develop a heat-related illness. Daily-wagers don’t go to hospitals unless their conditions are acute – because they’d lose a day’s earnings, because their out of pocket expenses have increased or both.

Do you think parts of India will become unliveable in your lifetime?

This is a good question. I’d say that ‘unliveable’ is a subjective thing. I have a friend in Seattle who recently bought a house in what she said was a nice part of the city, with lots of greenery, opportunities to go hiking and trekking on the weekend, with clear skies, clean air and large water bodies nearby. Liveability to her is different from, say, liveability to someone living in New Delhi, where the air is already quite foul, summers are very hot and winters are likely to become colder in future. Liveability means different things to people living in Delhi, London and Seattle. Many parts of India have been unliveable for a long time now, we just put up with it – and many people do because they don’t have any other option – and our bar just keeps slipping lower.

A new map of Titan

It’s been a long time since I’ve obsessed over Titan, primarily because after the Cassini mission ended, the pace of updates about Titan died down, and because other moons of the Solar System (Europa, Io, Enceladus, Ganymede and our own) became more important. There have been three or four notable updates since my last post about Titan but this post that you’re reading has been warranted by the fact that scientists recently released the first global map of the Saturnian moon.

(This Nature article offers a better view but it’s copyrighted. The image above is a preview offered by Nature Astronomy; the paper itself is behind a paywall and I couldn’t find a corresponding copy on Sci-Hub or arXiv nor have I written to the corresponding author – yet.)

It’s fitting that Titan be accorded this privilege – of a map of all locations on the planetary body – because it is by far the most interesting of the Solar System’s natural satellites (although Europa and Triton come very close) and were it not orbiting the ringed giant, it could well be a planet of its own accord. I can think of a lot of people who’d agree with this assessment but most of them tend to focus on Titan’s potential for harbouring life, especially since NASA’s going to launch the Dragonfly mission to the moon in 2026. I think they’ve got it backwards: there are a lot of factors that need to come together just right for any astronomical body to host life, and fixating on habitability combines these factors and flattens them to a single consideration. But Titan is amazing because it’s got all these things going on, together with many other features that habitability may not be directly concerned with.

While this is the first such map of Titan, and has received substantial coverage in the popular press, it isn’t the first global assessment of its kind. Most recently, in December 2017, scientists (including many authors of the new paper) published two papers of the moon’s topographical outlay (this and this), based on which they were able to note – among other things – that Titan’s three seas have a common sea level; many lakes have surfaces hundreds of meters above this level (suggesting they’re elevated and land-locked); many lakes are connected under the surface and drain into each other; polar lakes (the majority) are bordered by “sharp-edged depressions”; and Titan’s crust has uneven thickness as evidenced by its oblateness.

According to the paper’s abstract, the new map brings two new kinds of information to the table. First, the December 2017 papers were based on hi- and low-res images of about 40% of Titan’s surface whereas, for the new map, the authors write: “Correlations between datasets enabled us to produce a global map even where datasets were incomplete.” More specifically, areas for which authors didn’t have data from Cassini’s Synthetic Aperture Radar instrument for were mapped at 1:2,000,000 scale whereas areas with data enabled a map at 1:8,000,000 scale. Second is the following inferences of the moon’s geomorphology (from the abstract the authors presented to a meeting of the American Astronomical Society in October 2018):

We have used all available datasets to extend the mapping initially done by Lopes et al. We now have a global map of Titan at 1:800,000 scale in all areas covered by Synthetic Aperture Radar (SAR). We have defined six broad classes of terrains following Malaska et al., largely based on prior mapping. These broad classes are: craters, hummocky/mountainous, labyrinth, plains, lakes, and dunes [see image below]. We have found that the hummocky/mountainous terrains are the oldest units on the surface and appear radiometrically cold, indicating icy materials. Dunes are the youngest units and appear radiometrically warm, indicating organic sediments.

SAR images of the six morphological classes (in the order specified in the abstract)

More notes once I’ve gone through the paper more thoroughly. And if you’d like to read more about Titan, here’s a good place to begin.