According to a recent study published in the Journal of Geophysical Research: Atmospheres by astrobiolog Jacob Haqq-Misra and climate scientist Eric Wolf of the Seattle-based nonprofit Blue Marble Space, plant life on Earth is projected to survive for another 1.87 billion years. Utilizing three-dimensional climate models, the researchers simulated future climate changes driven by a steadily brightening Sun, finding that vegetation could endure nearly as long as the planet’s oceans despite challenges like carbon starvation and extreme surface heating.
Solar Luminosity Threatens Vegetative Biosphere
Plants currently account for about 80 percent of all biomass on Earth, requiring a precise balance of sunlight, water, and carbon dioxide to survive. According to Haqq-Misra and Wolf, this balance faces a ticking clock as the Sun ages and brightens. Their 3D climate models project conditions over the next two billion years, factoring in both increasing solar radiation and shifting atmospheric carbon dioxide levels.
Natural carbon cycling on Earth involves a carbonate-silicate cycle where atmospheric gas dissolves into oceans, settles into the sea floor as rock, and returns via tectonic and volcanic activity. Because the exact temperature sensitivity of this cycle remains uncertain, the researchers tested two distinct environmental scenarios to determine when plant life finally hits its limit.
Strong Weathering Versus Weak Weathering Models
Under the first scenario, dubbed the strong weathering model, surface temperatures remain relatively stable while atmospheric carbon dioxide plummets because geological processes absorb it faster than volcanoes replenish it. According to the study, plants will experience carbon starvation without sufficient CO₂, driving the entire vegetative biosphere to extinction approximately 1.84 billion years from now.
Under the second scenario, known as the weak weathering model, atmospheric carbon levels stay steady, but surging solar intensity drives global average surface temperatures up to roughly 65 degrees Celsius. At that thermal threshold, no known land plants can survive. This second simulation yields the maximum estimated plant lifespan of 1.87 billion years, suggesting photosynthetic life could persist almost until Earth loses its liquid oceans entirely.
Did you know? Today, plants make up about 80 percent of Earth’s total biomass. The new simulations indicate that Earth’s vegetation is more resilient to future environmental shifts than previously calculated in some past research models.
Potential for Plant Evolution and Technological Intervention
The simulation carries a major caveat: it excludes future plant evolution and potential technological interventions by humans or other intelligent civilizations. According to the researchers, evolutionary adaptations could allow plants to manage surrounding temperatures and pressures, enabling them to migrate to higher altitudes, stretch into the stratosphere, or even spread to low-gravity bodies like the Moon and comets.
Beyond natural adaptation, speculative geoengineering concepts could theoretically extend plant survival. Proposed technological fixes include deploying reflective aerosols in the upper atmosphere, positioning orbital sunshades to block incoming solar heat, or even altering Earth’s orbit and the Sun’s mass to stabilize planetary temperatures. Despite the extreme risks and speculative nature of such ideas, the study highlights the profound resilience of life.
“Life on Earth is extremely resilient,” the researchers wrote, noting that current physiological limits reflect today’s biosphere rather than absolute boundaries for how life might evolve. Ultimately, the team concluded that life will likely persist for as long as Earth itself remains physically capable of supporting it.
Frequently Asked Questions
When will plant life on Earth die out?
According to a study by Jacob Haqq-Misra and Eric Wolf published in the Journal of Geophysical Research: Atmospheres, the last plants on Earth are projected to die out approximately 1.87 billion years from now.
Why are plants expected to go extinct?
Plants face two primary threats from an aging, brightening Sun: carbon starvation due to geological carbon depletion, or extreme surface heating reaching roughly 65 degrees Celsius.
Did the simulation account for plant evolution?
No. The climate models intentionally excluded future plant evolution and potential technological interventions, which the authors suggest could theoretically allow life to adapt or spread beyond Earth.
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