The Earth's Inner Core
The inner core is the very center of the Earth, extending from the center of the planet to a radius of about 1,220 kilometers. It is made up primarily of solid iron and nickel with small amounts of other elements. Some key facts about the inner core:
- Spin and Rotation: The inner core rotates at a slightly different speed and direction compared to the rest of the Earth. This differential rotation may be caused by electromagnetic forces and the convection of the outer core. Over decades and centuries, the inner core's westward spin can periodically speed up and slow down in a phenomenon called inner core super-rotation.
- Structure and Composition: Seismic studies have revealed the inner core has an innermost center that is distinct from the outer part of the inner core. The innermost inner core is a solid ball about 300 km across and is composed of a crystal structure oriented North-South. The outer inner core has a more complex structure and composition.
- Temperature and Pressure: The inner core is under immense pressure from the overwhelming weight of the outer layers of Earth pushing inward. Scientists estimate the pressure ranges from 330 to 360 gigapascals. The temperature is similarly extreme, estimated to be about 5,700 K.
- Age and Crystallization: The inner core is thought to have begun crystallizing from the surrounding molten outer core about 0.5 to 1 billion years ago as the planet slowly cooled. This crystallization process released latent heat and light elements that drove convection in the outer core, creating Earth’s magnetic field through the geodynamo process.
- Importance to Earth's Magnetism: As the inner core grows, the release of heat, iron, and light elements fuels the geodynamo generating Earth's magnetic field which protects us from solar wind and cosmic radiation. Without our inner core, Earth’s magnetic field would eventually fade away.
Global Warming and Climate Change
Global warming refers to the long-term heating of Earth's climate system observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning which increases heat-trapping greenhouse gases like carbon dioxide in the atmosphere. Major global warming consequences and risks include:
- Ocean Warming and Acidification: Oceans absorb over 90% of the excess heat from greenhouse gas forcing, causing ocean warming and thermal expansion. This leads to rising sea levels. Oceans also absorb about 30% of human-caused carbon dioxide, making them more acidic and threatening marine ecosystems.
- Melting Polar Ice and Glaciers: Increased air and ocean temperatures melt glaciers and polar ice sheets, contributing to accelerating sea level rise. From 1992-2020, Greenland and Antarctic ice sheets lost an average of 149 billion metric tons of ice per year.
- Extreme Weather Events: Higher temperatures increase the frequency, intensity and duration of heatwaves, heavy precipitation events, floods, and tropical storms by altering atmospheric conditions, moisture levels, and ocean temperatures that fuel extreme weather.
- Biodiversity Loss and Ecosystem Damage: Climate change shifts ecosystem boundaries, alters habitats, breeding and migration patterns, increases invasive species, megafires, and tree death. This drives biodiversity loss and species extinction risks. About half of all species face local extinction at 2°C of warming if they cannot relocate.
- Threats to Human Health and Food Security: Health risks include heat stress, poor air quality, reduced food nutrition, increased diseases like malaria, dengue fever impacting hundreds of millions more people per year. Crop yields decline with extreme heat, drought, and changes in rainfall; hunger and malnutrition risks go up.
- Economic and Societal Disruption: Climate change causes trillions in estimated economic damage, affecting trade, tourism, disaster resilience, infrastructure, agriculture, fisheries. It can exacerbate poverty, conflict and war, mass migration from displaced populations.
The impacts grow exponentially worse at higher levels of warming. Scientists warn limiting warming to 1.5°C instead 2°C can help avoid some of the most catastrophic and irreversible risks.
Human Behavior and Thinking
Psychologists categorize human thinking into two systems:
System 1: Fast, automatic, frequent, emotional, stereotypic thinking
System 2: Slower, conscious, logical, reasoned thinking
When making judgments related to climate change, mental shortcuts and emotions can distort perceptions of risk or urgency (System 1). Ideology, motivated reasoning, confirmation bias and influences from peers or media can further hamper accurate scientific judgments. On the other hand, scientific information about climate change risks often does not incite enough concern or personal relevance to mobilize action.
Both analytical and affective processes shape climate change risk perceptions and behaviors. To enable society-wide mobilization on climate change involves communicating scientific facts clearly, as well as connecting the issue to people’s lives and values on an emotional level through stories, images and experiences. Context also plays a major role. Social norms, cultural values, geographic vulnerability, governance and other societal factors vary climate concern and policy support across the globe.
Overcoming the tendency for short-term thinking also poses a barrier to properly evaluating multi-generational climate risks. Psychologists are studying how emotional images depicting potential future scenarios, interactions with affected communities, or simulations of personal losses from “pre-traumatic” climate events may spur wider engagement.
Emergentism and Master Mind Theories
Emergentism is the philosophical theory that at a certain level of complexity, entities acquire new properties that cannot be predicted from the components alone. In other words, the whole is greater than the sum of its parts. In human psychology, it suggests human consciousness originates from the connections between billions of neurons working together in the brain.
Some philosophers have proposed variations on emergentist themes to suggest forms of collective intelligence or consciousness could emerge from humans interacting in societies over generations. This “master mind” type emergence is used by some to argue there may be an inherent trajectory towards increasing intelligence, problem-solving or moral progress in human civilization.
However, these ideas remain highly speculative philosophically and scientifically controversial due to lack of evidence. Critics argue we cannot extrapolate notions of progress or higher intelligence as inevitable. Human history shows moral progress is not guaranteed - our civilization still faces risks of collapse, warfare, or lost knowledge from ignoring climate change warnings from science. Survival is not ensured. Sustainable solutions require conscious, ethical choice and action.
In summary, facing the climate crisis involves heeding warnings from Earth system science to transition energy, transport, finance, agriculture, and consumption patterns worldwide to limit warming to 1.5°C. It also requires understanding the cognitive and social dynamics that shape public engagement, policymaking and collective action. There are risks of civilization collapse if warming continues unchecked, but also potential for an unprecedented global mobilization to build a more sustainable future. However, human survival and moral progress are not inevitable. They require making conscious choices now that protect future generations based on reason, science and compassion.
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