Back in 2022, Tildes helped me build my current PC (Thanks everyone!). Back then I knew that eventually I would have to replace my motherboard, which underwent corrosion and became unreliable. I never turn off or even put my PC to sleep because, otherwise, it won't turn on for hours. I'd like to change that. I'm pretty confident that is an issue with the motherboard, which underwent repairs before. Other components are much newer and my power source is top notch.

Here's the machine on PC Part Picker. Should I just buy the same motherboard again? I mean, I don't have any complaints, I just happened to live by the sea back then, leading to premature failure. But it's still working. It's cheap, too.

I might be up for a better processor, but price is a concern. What would be the next affordable step from what I have now? In any case, the CPU is rarely an issue for any of my tasks, and the only game I play that could use a more powerful processor is World of Warcraft, which I only play intermittently anyway. Maybe it isn't worth it.

I'm getting a 1TB SSD, those seem to have gotten much cheaper since 2022!

Because, unlike me, most Tildes users are in the US, Canada, and Europe, when taking prices into account, multiply them by 5 in your head to have a sense of what that expense means in my country.

Thanks!

What have you been watching and reading this week? You don't need to give us a whole essay if you don't want to, but please write something! Feel free to talk about something you saw that was cool, something that was bad, ask for recommendations, or anything else you can think of.

If you want to, feel free to find the thing you're talking about and link to its pages on Anilist, MAL, or any other database you use!

This is a recurring post to discuss programming or other technical projects that we've been working on. Tell us about one of your recent projects, either at work or personal projects. What's interesting about it? Are you having trouble with anything?

This is my attempt at contributing to "A Layperson's Introduction" series, here on Tildes. It's why it's here on ~science, rather than ~enviro

Many people have heard about how global warming works. “We are emitting greenhouse gases, and these trap heat, leading to further warming.” So how does this process occur in more detail? What is its physical basis? In this post, I will try to explain the physical basis of these questions in a simple way that is a bit more detailed than what is usually seen.

Electromagnetic Spectrum and Thermal Radiation

The electromagnetic spectrum is a broad spectrum that includes visible light. There are long wavelengths, such as radio waves and infrared light, and short wavelengths, such as ultraviolet light, X-rays, and gamma rays.

Visualization of the electromagnetic spectrum

Thermal radiation is the radiation emitted by the molecules of an object due to thermal movement. It can be in the visible light wavelength, shorter wavelength, or longer wavelength. The length of these wavelengths varies depending on the temperature of the object that is the source of thermal radiation. For example, the thermal radiation emitted by Earth falls into the infrared spectrum, which is at lower energy, because Earth is not as hot as a star. The shift of thermal radiation emitted by colder objects to longer wavelengths is also known as Wien's law.

Energy Budget and Stefan-Boltzmann Law

Our planet Earth has a certain energy budget. In other words, the energy coming to the planet and the energy going out from the planet are specific. The source of the energy coming to the Earth is the Sun, and on average, approximately 340 Watt/m² energy reaches the surface of the planet. In order for this energy to be balanced, the energy radiated from Earth into space must be equal to this amount. This happens in two ways. First, some of the incoming energy is reflected into space by the Earth itself. Both the atmosphere (especially clouds) and the surface make this reflection. The second part can be explained by a physical law called Stefan Boltzmann law. According to this law, each object emits a certain amount of energy as thermal radiation, and the amount of this energy increases with temperature. This increase does not occur linearly, but as the fourth power of temperature. The mathematical expression of the law is given below.

E = σT⁴

In this equation, "E" is the energy, "σ" (sigma) is the Stefan-Boltzmann constant, and "T" is the temperature in Kelvin. However, the law cannot be applied to any object in its current form. The above equation is valid for ideal bodies called "black bodies". In physics, a black body is the name given to an ideal body that absorbs and emits all incoming radiation. However, Earth differs from a black body due to reflection. Therefore, the following equation is more appropriate.

E = εσT⁴

Here, ε (epsilon) means emissivity. Emissivity is the effectiveness of the surface of a material in emitting energy as thermal radiation. For a black body, ε = 1. The Earth's mean ε is less than 1, because it is not a black body. At the same time, emissivity changes depending on which part of the Earth is examined. For example, the emissivity of a vegetated surface and a desert or glacier are different. However, it is more important for us at this point to remember that the mean ε is less than 1.

When we look at the formulae above, we see that, in accordance with the Stefan-Boltzmann law, the Earth emits thermal radiation depending on the temperature, even though it is not a black body. This constitutes the second part of the Earth's energy budget, namely thermal radiation. In summary, Earth receives energy from the Sun and radiates this energy through reflection and thermal radiation.

Radiative Forcing and Greenhouse Effect

The energy budget is very important for our planet. Any change in the budget causes Earth to warm or cool. Natural or human-induced changes that change the balance between incoming and outgoing energy are called radiative forcing. This is the mechanism by which greenhouse gases warm the planet. Some gases in the atmosphere, such as carbon dioxide (CO²) or methane (CH⁴), have physical properties that absorb the thermal radiation emitted by Earth. If you remember, Earth's thermal radiation was in the infrared spectrum. That is, these gases absorb at certain points in the infrared spectrum. As a result of this absorption, the gases emit it again in the form of thermal radiation in all directions. While some of the emitted radiation escapes into space, some of it remains on Earth, causing warming. Since the energy emitted by Earth will increase as it warms up, at a certain point, the incoming and outgoing energy becomes equal again.

CO² emissions, concentration, and radiative forcing

In the image above, in different climate change scenarios, emissions of the greenhouse gas CO²) (left), the corresponding increase in CO² concentration in the atmosphere (middle), and the increasing radiative forcing due to this increase are shown (right). Note that the radiative forcing is shown in Watts/m². It is shown this way because it is calculated based on the change in Earth's energy budget, and Earth's energy budget is shown as Watt/m².

In other words, although the incoming energy is the same, there is a certain decrease in the energy going into space due to the greenhouse effect. This leads to what we call radiative forcing. As a result of radiative forcing, the temperature of Earth increases, and as the temperature increases, the thermal radiation energy emitted by the planet increases. This causes the incoming and outgoing energy to become equal again. As a result, in the long run, radiative forcing (and the greenhouse effect) does not lead to a change in the energy budget. However, it causes solar energy to remain in the atmosphere for a longer period of time, causing a certain amount of warming. This is what we call global warming due to the greenhouse effect.

This process is, of course, more complex than described here. Since the atmosphere has a layered and fluid structure, there are factors that make the job more complicated. For example, while the increase in CO² warms the troposphere (what we call global warming), the lowest layer of the atmosphere, it causes the stratosphere, its upper layer, to cool. Despite these and similar complexities, the physical basis of global warming is still based on the mechanisms described in this post.

Sources

• Schmittner, A. (2018). Introduction to Climate Science. Oregan State University
• van Vuuren, D. P., Edmonds, J., Kainuma, M., Riahi, K., Thomson, A., Hibbard, K., Hurtt, G. C., Kram, T., Krey, V., Lamarque, J.-F., Masui, T., Meinshausen, M., Nakicenovic, N., Smith, S. J., & Rose, S. K. (2011). The Representative Concentration Pathways: An overview. Climatic Change, 109(1-2), 5–31. https://doi.org/10.1007/s10584-011-0148-z
• Wild, M., Folini, D., Schär, C., Loeb, N., Dutton, E.G., König-Langlo, G. (2013). The global energy balance from a surface perspective. Clim Dyn 40, 3107–3134. https://doi.org/10.1007/s00382-012-1569-8
• Zohuri, B., McDaniel, P. (2021). Basic of heat transfer. Introduction to Energy Essentials, 569–578. https://doi.org/10.1016/b978-0-323-90152-9.00017-7

Image Sources

• Image 1: https://science.nasa.gov/ems/01_intro/
• Image 2: van Vuuren et al., 2011

As the title suggests, I am looking for a free chrome or firefox plugin that can locally scrape data from multiple URLs. To be a bit more precise, what I mean by it:

• A free chrome or firefox plugin
• Local scraping: it runs in the browser itself. No cloud computing or "credits" required to run
• Scrape data: Collects predefined data from certain data fields within a website such as https://www.dastelefonbuch.de/Suche/Test
• Infinite scroll: to load data that only loads once the browser scrolls down (kind of like in the page I linked above)

I am not looking into programming my own scraper using python or anything similar. I have found plugins that "kind of" do what I am describing above, and about two weeks ago I found one that pretty much perfectly does what is described ("DataGrab"), but it starts asking to buy credits after running it a few times.

My own list:

• DataGrab: Excellent, apart from asking to buy credits after a while
• SimpleScraper: Excellent, but asks to buy credits pretty much immediately
• Easy Scraper: Works well for single pages, but no possibility to feed in multiple URLs to crawl
• Instant Data Scraper: Works well for single pages and infinite scroll pages, but no possibility to feed in multiple URLs to crawl
• "Data Scraper - Easy Web Scraping" / dataminer.io: Doesn't work well
• Scrapy.org: Too much programming, but looks quite neat and well documented

Any suggestions are highly welcome!

Edit: A locally run executable or cmd-line based program would be fine too, as long as it just needs to be configured (e.g., creating a list of URLs stored in a .txt or .csv file) instead of coded (e.g., coding an infinite scroll function from scratch).

Have you watched any movies recently you want to discuss? Any films you want to recommend or are hyped about? Feel free to discuss anything here.

Please just try to provide fair warning of spoilers if you can.

I've been doing a lot of work with my therapist and it has been suggested that I might have a mix of both Autism and ADHD.

I have always related to Autism to a certain extent but I would never say it because I felt like I didn't really fit because some things I do don't make sense it that context. I was also obsessed with learning to be human since young and have a lot of systems to deal with it and apparently that means I've been masking for a very long time.

But my therapist also brought up ADHD and that has explained a lot about some the things I'm still currently struggling with. But again, when I look it up, I don't feel like I fully fit. But also, I have developed a lot of systems over the years to deal with my issues and function like a normal human being. So a lot of the things I struggle with is hidden because I've "fixed" them.

I'm still reluctant to say I have either of those two things because I feel like an imposter. So I've just settled on Neurodivergent and think that I can always learn the tools that help people with ADHD even if I don't have it. Because if the tools work for you, then why not?

But my therapist has suggested getting diagnosed because it does change what kind of medication you might get. I'm currently on medication for anxiety and depression.

So now I'm wondering how common it is to have a mix of both ADHD and Autism. For those who have both, what is it like for you? What is your daily life like? What are your struggles and how do you deal with them? When did you realise you might have a mix of both? How do you feel about yourself and your brain?

I apologize if this isn't the right place to ask this. I don't post very often and am getting used to it.

I'd define decent as the minimum expectation I have for having someone in my life. I use the term a lot, but I had never been clear on what I mean by it. I think for me its that the person broadly reciprocates the work I put into the relationship, both in kind and degree, unless I explicitly say otherwise. I'd say most of my interpersonal problems would fit under this; mainly being expected to put in a lot of emotional effort, and either they don't reciprocate it at all, they unambiguously do not match it or they ignore me when I tell them I don't care about gifts and act like the infrequent gift makes us equal.

But that's me, and I expect there are many more varied expectations from y'all. So, what make some a decent person to you?