Tag: earth

Humans are 0.01% of Biomass

Anyone who has walked through a jungle or wandered a grassland may already have guessed that humans are a pretty small part of Earth’s organic matter. The carbonaceous winners are plants, which make up 80% of all biomass on Earth. Bacteria comes in second at 13% and fungus is third at just 2%. Of the 550 gigatons of biomass carbon on Earth, animals make up ~2 gigatons, with insects comprising 50% of that and fish taking up 0.7 gigatons. Everything else, including mammals, birds, nematodes and mollusks are ~0.3 gigatons, with humans weighing in at 0.06 gigatons. “The fact that the biomass of fungi exceeds that of all animals’ sort of puts us in our place”

Underworld Continents

Giant blobs nestled deep in the Earth may influence everything from the structure of island chains to mass-extinction events. If buoyed to the surface, they would be hot enough to cause gigantic, sustained eruptions. In turn, that volcanism could have changed the climate and even led to mass extinctions. Such a sequence, if verified, would be the ultimate antediluvian time bomb — apocalyptic extinctions triggered by subterranean structures buried since the birth of the world.

The Greening Earth

The earth is getting greener, in large part due to increased CO2 in the atmosphere. Surprisingly, however, another driver is programs in China to increase and conserve forests and more intensive use of cropland in India.

2022-07-21: While Amazon deforestation continues, in other places it is reforestation.

England has 2x the amount of forestland in the past 150 years, and now has as much land dedicated to forests as the year 1350.

Space Radar

Capella’s high revisit x-band constellation with InSAR capability will capture millimeter-scale change’s on the Earth’s surface. Interferometric synthetic aperture radar is a radar technique used in geodesy and remote sensing. This geodetic method uses 2 or more synthetic aperture radar (SAR) images to generate maps of surface deformation or digital elevation, using differences in the phase of the waves returning to the satellite or aircraft. The technique can potentially measure millimeter-scale changes in deformation over spans of days to years. It has applications for geophysical monitoring of natural hazards, for example earthquakes, volcanoes and landslides, and in structural engineering, in particular monitoring of subsidence and structural stability.

Subsurface biomass

70% of Earth’s bacteria and archaea live in the subsurface

Barely living “zombie” bacteria and other forms of life constitute an immense amount of carbon deep within Earth’s subsurface—245-385x greater than the carbon mass of all humans on the surface

2023-07-27: Dark Oxygen

In groundwater reservoirs 200 meters below the fossil fuel fields of Alberta, Canada, they discovered abundant microbes that produce unexpectedly large amounts of oxygen even in the absence of light. The microbes generate and release so much of what the researchers call “dark oxygen” that it’s like discovering “the scale of oxygen coming from the photosynthesis in the Amazon rainforest”. The quantity of the gas diffusing out of the cells is so great that it seems to create conditions favorable for oxygen-dependent life in the surrounding groundwater and strata. Instead of taking in oxygen from its surroundings like other aerobes, the bacteria created its own oxygen by using enzymes to break down the soluble compounds called nitrites (which contain a chemical group made of nitrogen and 3 oxygen atoms). The bacteria used the self-generated oxygen to split methane for energy. When microbes break down compounds this way, it’s called dismutation. Until now, it was thought to be rare in nature as a method for generating oxygen.
Jupiter’s moon Europa has a deep, frozen ocean; sunlight may not penetrate it, but oxygen could potentially be produced there by microbial dismutation instead of photosynthesis.