Dr. Gavin A. Schmidt, Director of NASA's Goddard Institute for Space Studies, discusses how paleoclimate records and Earth system models reveal the interaction between natural climate variability and human-driven greenhouse gas emissions. He explains the scientific challenge of distinguishing climate signals from natural noise in projections, noting that weather remains unpredictable beyond 10-14 days while longer-term climate patterns respond to external forcings like orbital changes and volcanic eruptions. Schmidt emphasizes that the future climate trajectory depends on human choices made within present uncertainties.
Researchers discovered previously unknown microorganisms in coastal seafloor sediments that produce methane using naturally occurring conductive particles like magnetite as electron-exchange pathways. A new bacterium and methanogen species form a microbial network through these particles, representing an overlooked methane-production mechanism that may need inclusion in climate models.