This chapter describes different modeling approaches to understand the space environment and make space weather forecasts. Different types of models from toy models and empirical models to physics-based models are described and how they are used to understand space. The two major approaches to modeling the space environment – kinetic or magnetohydrodynamic – are described. After defining new statistical and machine learning approaches, a supplement explores Carl Sagan’s list of logical fallacies that are useful for assessing the strengths and weaknesses of arguments.

Climate modeling requires supercomputers, which are simply the most powerful computers at a given time. The history of supercomputing is briefly described. As computer chips became faster each year for the same price (Moore’s Law), supercomputers also became faster. But due to technological limitations, chips are no longer becoming faster each year. More chips are therefore needed for faster supercomputers, which means that supercomputers cost more money and consume more power every year. The newest chips, known as Graphical Processing Units (GPUs), are not as efficient at running climate models, because they are optimized for other applications like machine learning (ML). Extrapolating current trends in computing, we can expect future supercomputers that run the high-resolution climate models of the future to be very expensive and power hungry.

A shorter version of this essay was originally published in the Los Angeles Times opinion editorial pages on July 22, 2008, as “Toward a Type 1 Civilization: Along with energy policy, political and economic systems must also evolve.” This essay is about how we can transition from a zero-sum tribal world to a nonzero global world.

looks at the impact digital technology is having on the way people communicate and how this has given rise to emoji culture. One of the key ways in which technology has an effect on language is in terms of what it does and doesn’t allow people to do. People adapt their language practices to the constraints imposed by the available technology, and, over time, these practices develop into linguistic conventions. Emoji are an archetypal product of the role technology plays in our life - they’re intimately tied to the devices we use to communicate. But they’re also a product of social media culture and of the way this technology has brought about a new informality in the way we write to each other. This chapter looks at how emoji fit within this larger context, as well as how features of human-computer interaction such as auto-predict are integrating these technologies ever more into the infrastructure of our daily lives.