Four For Friday | Dec 5, 2025

LF199 | Climate models that ignore wellbeing, a new healthspan metric: Joy, cities as climate champions, Japan invests $65bn in AI + Michael Lindenmayer's message: Give A Sh*t.

Welcome to this week’s Four For Friday - nuggets of interesting things I’ve picked up this week, plus a cultural amuse bouche for the weekend.

1. Climate models miss the point

Heat now kills 550,000 people annually, up 63% since the 1990s, yet the climate models that guide global policy making actually ignore human wellbeing.

The Lancet study finds that while researchers have documented climate’s toll on mental health, infectious disease, worker productivity, conflict, and migration, the computer simulations that governments use don’t register these factors.

The research shows malaria, depression, lost working hours, and food insecurity are systematically excluded - as per this article. We’re optimizing for temperature targets while accidentally undervaluing the benefits of keeping humans alive and functional.

So what? A classic technocratic blind spot: measuring what’s quantifiable rather than what’s consequential. We need new metrics.

2. New healthspan metric: Joy

Speaking of new metrics… A group connected to San Francisco’s hacker-forward Frontier Tower (previously featured in LF) is attempting to create the first unified metric for joy, connection and synchrony.

The write up suggests that emotional experiences modulate stress biology as reliably as sleep deprivation or inflammatory diets. Participants will wear single-ear EEG sensors while researchers measure oxytocin, CRP, and other biomarkers across two nights: one baseline, one “Science Rave” (courtesy of longevity raver, Tina Woods) involving rhythmic entrainment and synchronized movement. The premise is that loneliness shortens telomeres and chronic disconnection elevates inflammation, so why shouldn’t joy get its own biomarker?

The goal is to create a metric that sits alongside step count, HRV and sleep score longevity. Whether quantifying collective effervescence survives contact with rigorous data remains delightfully uncertain, but what a refreshing and interesting project!

The So What? If validated, JoyScore could shift longevity medicine from molecular precision toward measuring emotional and social environments as health inputs.

3. The City-Industry-Climate Nexus

A UNIDO white paper argues that decarbonizing cities is not just environmental policy but a strategic industrial agenda.

Cities consume most of the world’s energy and generate the majority of greenhouse gas emissions, yet they’re also frontline implementers of climate solutions. The paper introduces the “city-industry-climate nexus,” where infrastructure, production systems, value chains, and climate action converge.

The So What? By applying systems thinking to urban decarbonization, cities become engines of innovation and resilience, not just sites of risk. A blueprint for inclusive net-zero futures, perhaps.

4. Japan’s $65bn AI bet

Japan has a well-deserved reputation for being conservative about innovation, but when the move, they move.

They’ve just announced a massive ¥10 trillion ($65 billion) investment plan to boost domestic AI and semiconductor industries by 2030. The goal? “AI sovereignty”—reducing dependence on the US and China by building a world-class domestic ecosystem. This conversation is happening in capitals around the world as the realities of being dependent on the US or China hit home.

The plan targets foundational models, supercomputing, next-gen chip manufacturing and quantum computing. This “techno-nationalism” mirrors the US CHIPS Act and China’s state-driven tech push, with the government acting as a mega-VC.

Japan is deploying earthquake-resistant data centers, 40 operational submarine cables, and massive GPU arrays into what Prime Minister Ishiba calls “the first year of quantum industrialization.” SoftBank alone is committing over $40 billion through its Stargate partnership with OpenAI Introl, while domestic firms like Fujitsu and NEC build enterprise-grade AI platforms. The timing is strategic: Japan’s aging demographics create demand for automation without triggering job displacement anxieties. The country faces a projected 789,000 software engineer deficit by 2030, so the government has allocated another trillion yen for workforce reskilling. It’s a quintessentially Japanese approach: bold infrastructure investment wrapped in pragmatic regulations. Less flashy than some, but certainly substantive.

The So What? Japan is positioning itself as the stable, disaster-resilient alternative to US-China AI dominance, leveraging demographic necessity as competitive advantage.

+ Something-4-The-Weekend

Sharing this TEDx Fukuoka video to lift up your sights and offer inspiration. It’s from a few years ago by my new colleague Michael Lindenmayer, a Swiss-American impact innovator with whom I’m currently collaborating to build out smart, preventive health bathrooms.

2.5 billion people lack safe toilets. Every 17 seconds a child dies from sanitation-related disease. Michael shares lessons for solving super-sized problems, forged from collaboration with the Gates Foundation and World Bank, among others: talk about uncomfortable truths, show courage (like Dr. Snow breaking London’s cholera pump), invent creatively (toilets on motorbikes, anyone?), tinker relentlessly, and stay humble.

The punchline? Poop isn’t intrinsically bad. Put it in the wrong place and you’ve got a death zone. Put it in the right place and you’ve got insights, power, fertilizer, and dignity. In sum, he wants you to give a sh*t about solving super scale problems, and believes we all can.

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That’s all for now - happy weekend everyone.

- Stephen