These new findings could help scientists adapt crops to dry environmental conditions in the future. Plants rely on sunlight to turn water and carbon dioxide into energy-rich sugars and oxygen through different forms of photosynthesis. Drought can make that process far more difficult. A research group led by Wolfram Weckwerth at the University of Vienna [...]

The economist John Maynard Keynes once remarked, “In the long run we are all dead.” From an astronomical standpoint, this is true for the Earth itself. In roughly 5 billion years, the Sun will exhaust the hydrogen at its core and enter the next phase of its life as a Red Giant, where it will swell up large enough to engulf and destroy the Earth.

Currently, the Sun is still in its main-sequence phase, where it fuses hydrogen into helium in its core. Although it remains relatively stable during this phase, it will gradually grow brighter with time. As the Sun shines brighter, the increased heat and radiation will raise Earth’s surface temperature, potentially pushing it past the threshold for life to survive. 

One of Earth’s geological processes that helps regulate its surface temperature is the carbon cycle. Over millions of years, carbon moves from the Earth’s interior into the atmosphere as carbon dioxide or CO₂, where it functions as a greenhouse gas that traps heat. Plants take in this CO₂ through photosynthesis and move carbon through the biosphere. 

Meanwhile, rain and rock weathering draw carbon into the oceans and rocks. By pulling CO₂ out of the atmosphere, the carbon cycle could mitigate Earth’s warming as the Sun brightens over time. Today, human activities are increasing atmospheric CO₂ and warming the planet. However, over billions of years, the carbon cycle could gradually remove enough CO₂ from the atmosphere that eventually too little would remain to support photosynthesis. 

With these challenges to life on Earth in mind, the researchers Jacob Haqq‐Misra and Eric Wolf investigated how long Earth’s biosphere could last in the distant future. The team used computer models to calculate the balance of energy that Earth would receive and emit over time, accounting for the effects of increasing sunlight and changing atmospheric CO₂ concentrations. They followed this up with calculations using the ExoCAM model to determine the temperature and atmospheric conditions of future Earth across different latitudes. They related these conditions to a habitability metric to determine their impact on the biosphere.

To estimate the biosphere’s maximum possible lifespan, the team conducted 29 simulations representing the planet’s conditions over the next 2 billion years. In one set of simulations, the Earth’s carbon cycle contributed little to regulating surface temperature, with the atmosphere’s CO₂ concentration fixed at approximately modern levels of 400 parts per million (ppm) and surface temperatures continuing to increase. In another, the carbon cycle worked to keep Earth’s average surface temperature fixed at the modern average of approximately 59℉ (15℃), no matter how much it had to reduce CO₂ in the atmosphere. 

In the scenario with a fixed CO₂ concentration, the team found that in 1.7 billion years, Earth’s surface reached an average of 122°F (50°C), which is too hot for most land plants. After 1.9 billion years, it reached 149°F (65°), becoming too hot for all land plants to survive as temperatures continued to rise. 

They also found that in the fixed average surface temperature scenario, atmospheric CO₂ dropped below the 150 ppm level that most plants require for photosynthesis within 500 million years. After 1.4 billion years, CO₂ levels fell below 10 ppm, leaving only a few land photosynthesizers and aquatic plants alive. After about 1.8 billion years, atmospheric CO₂ dropped to 1 ppm, leaving only microbes capable of photosynthesis.

The researchers’ findings generally extend the estimated lifetime of Earth’s future biosphere compared with earlier, simpler models that suggested maximum lifespans of 100 million to 1.5 billion years. However, they clarified that other scientists should verify their results by running tests with other models, especially under extreme conditions of high incoming solar radiation and low atmospheric CO₂. 

Lastly, Haqq‐Misra and Wolf noted that their model did not account for major evolutionary changes that could help life adapt to future conditions. Over time, plants could evolve to tolerate higher temperatures or lower atmospheric CO₂ levels. Future humans or another intelligent species might also engage in large-scale geoengineering projects to prevent the end of life on Earth. If life on Earth proves adaptable enough, the biosphere may endure until a Red Giant fills the daytime sky.

The post The long-term fate of Earth’s biosphere appeared first on Sciworthy.

He received a 1992 Nobel Prize for developing a theory that explained fundamental processes behind photosynthesis, respiration, oxidation and even how fireflies produce light.

A new study reveals that oak trees can keep photosynthesizing for months after growth ends, challenging assumptions about how effectively forests convert absorbed carbon into long-term storage. A tree can look busy long after it has stopped building itself. Its leaves may still be absorbing sunlight and pulling carbon dioxide from the air, but deep [...]

Researchers in Japan have developed a new artificial photosynthesis system that can produce solar fuel more reliably under changing sunlight conditions without using batteries. The team from Osaka Metropolitan University says the technology could make solar fuel systems simpler, cheaper, and more practical for everyday use. Artificial photosynthesis is inspired by the process that plants […]

The post New artificial photosynthesis system makes solar fuel without batteries appeared first on Knowridge Science Report.

A self-regulating artificial photosynthesis system makes solar fuel without batteries, offering a simpler and potentially cheaper path to clean energy storage. Researchers at Osaka Metropolitan University have created a new artificial photosynthesis system that can produce solar fuel more consistently while eliminating the need for battery-based control systems. The advance comes from incorporating a self-regulating [...]

The recent claim that polymetallic deep-ocean floor nodules produce oxygen challenges traditional views on oxygen production and the origin of life. New evidence suggests oxygen is produced in darkness via electrolysis in these nodules, sparking controversy and skepticism in the scientific community regarding its implications for evolution of life.

Day 3 of creation, God formed dry land and initiated life with green plants, establishing essential conditions for future sentient life forms. This day also included the formation of Earth's physical structures. All creations were designed perfectly, paving the way for environmental balance and the development of biodiversity.

The fundamental differences between Carbon and Silicon as bases for life are presented. All known life relies on Carbon for energy through processes like photosynthesis, whereas Silicon-based life is impossible. The belief in creating sustainable fuels while eliminating Carbon is contrary to all logic. No Carbon means no life!

Water vapour and clouds are very important in regulating Earth’s temperature and supporting life. I question why the Climate Cult's focus is primarily on carbon dioxide. I emphasize the role of the essential molecules in the planet’s design and climate regulation.