Atmospheres, Climate, Weather Archives

Carnduff-2 stratigraphic and lithological data from refs. 13,25; MoEF data from ref. 13; Schandelah-1 stratigraphic and lithological data from refs. 23,24; Hebelermeer-2 stratigraphic data from ref. 6. (A), abundant; (C), common; Con, Contorta Beds; FCO, first common occurrence; FO, first occurrence; LCO, last common occurrence; LO, last occurrence; Mb., Member; Ps., Psilonoten sandstone; M, main; I, initial; P, precursor (pertaining to carbon isotope excursions). Green dashed line represents minimum δ98MoSW. MoEF calculations detailed in Methods. -- Nature/Trinity College Dublin

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Press Release

Deoxygenation Levels Similar To Today’s Played A Major Role In Marine Extinctions During Earth’s Major Past Climate Change Event

by Keith CowingNovember 27, 2023

Scientists have made a surprising discovery that sheds new light on the role that oceanic deoxygenation (anoxia) played in one of the most devastating extinction events in Earth’s history. Their […]

Eruption of the Hunga Tonga-Hunga Ha'apai volcano in the South Pacific on January 14, 2022, one day prior to the larger eruption plume that would significantly impact stratospheric composition. (Tonga Geological Services, Adapted from Wikimedia Commons, CC BY 3.0)

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Press Release

Massive 2022 Hunga Tonga-Hunga Ha’apai Eruption Reduced Earth’s Ozone Levels

by Keith CowingNovember 26, 2023November 26, 2023

When the Hunga Tonga-Hunga Ha’apai volcano erupted on January 15, 2022 in the South Pacific, it produced a shock wave felt around the world and triggered tsunamis in Tonga, Fiji, […]

True N2-dominated planet-to-star flux ratio spectrum with an assumed S/N = 20 (red) plotted against 1000 randomly sampled retrieved spectra with 95% confidence intervals. The blue spectrum is the median spectrum created from the 1000 plotted model runs that make up our confidence interval. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Constraining Background N2 Inventories On Directly Imaged Terrestrial Exoplanets To Rule Out O2 False Positives

by Keith CowingNovember 24, 2023November 24, 2023

Direct imaging spectroscopy with future space-based telescopes will constrain terrestrial planet atmospheric composition and potentially detect biosignature gases. One promising indication of life is abundant atmospheric O2.

An artist’s rendering of the warm exoplanet WASP-80 b whose color may appear bluish to human eyes due to the lack of high-altitude clouds and the presence of atmospheric methane identified by NASA’s James Webb Space Telescope, similar to the planets Uranus and Neptune in our own solar system. Image credit: NASA.

Astrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Press Release

Methane And Water Found In The Atmosphere Of Exoplanet WASP-80 b

by Keith CowingNovember 22, 2023November 22, 2023

NASA’s James Webb Space Telescope observed the exoplanet WASP-80 b as it passed in front of and behind its host star, revealing spectra indicative of an atmosphere containing methane gas […]

A summary of planet properties at the onset of XUV photoevaporation from models in Figure 6 with constant equilibrium temperatures of 600K, 900K, 1200K, and 1500K in blue, green, orange and red respectively. We assume the disc disperses at 𝑡disp = 3 × 106 yrs with a disc dispersal timescale of 𝜏disp = 105 yrs, all of which lead to XUV photoevaporation dominating at ∼ 4 Myrs, which coincides with the local protoplanetary disc having completely dispersed in these models. The left-hand panel shows the atmospheric mass fraction. Green lines with squares represent results from Owen & Wu (2016), for which boil-off was performed at 900K with initial atmospheric mass fractions of 0.3 and 0.1 in dot-dashed and dotted lines, respectively (note that initial atmospheric mass fractions in our models are calculated self-consistently through gaseous accretion). The right-hand panel shows planet sizes, including those that have been stripped of their atmosphere (atmospheric mass fraction < 10−4 ) and sit on an Earth-like composition line (grey dashed). This panel can be interpreted as a primordial mass-radius distribution. -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Status Report

Under The Light Of A New Star: Evolution Of Planetary Atmospheres Through Protoplanetary Disc Dispersal And Boil-off

by Keith CowingNovember 22, 2023November 22, 2023

The atmospheres of small, close-in exoplanets are vulnerable to rapid mass-loss during protoplanetary disc dispersal via a process referred to as `boil-off’, in which confining pressure from the local gas […]

(a) Surface temperature Ts (filled contours) for surface pressure ps = 5 bar and global mean surface optical depth τ = 5. The topography is plotted in blue dashed lines with a contour interval of 1000 m from 1000 m to 5000 m. The horizontal red dashed lines indicate the zone for tropical averaging (see Section 2.2). (b) Same as (a), but for the case with ps = 0.01 bar and τ = 0.01. The horizontal white dashed lines indicate the tropical averaging zone. (c) Relative surface lapse rate, γ (defined in Eq. 5), as a function of greenhouse effect, τ , and atmospheric thickness, ps. The data is sampled on a log-scale grid with τ = 0.003, 0.01, 0.1, 0.3, 1, 3, 5 and ps = 0.01, 0.1, 1, 5 bar. (d) The dependence of γ on τ when ps = 1 bar. Red solid (def): default simulation, obliquity equals zero, no atmospheric condensation, idealized topography, sensible heat flux enabled. Blue solid (obl20): as def, but with obliquity set to 20◦ . Blue dotted (atmo cond): as def, but with obliquity set to 20◦ , and a CO2-like atmospheric condensation is enabled. Magenta (MOLA): as def, but with Mars Orbiter Laser Altimeter topography. Cyan solid (w/o SH): as def, but with sensible heat flux disabled. Red dotted (2-column model): calculations from the simple two-column model (see Section 3.4). (e) As (d), but with varying ps and fixed τ = 0.1. Cyan dotted (fixed ρ in SH): as def, but the value of air density, ρ, is held fixed at the reference value for a 1-bar atmosphere in Eq. (3). -- astro-ph.EP

Arctic / Antarctic / Alpine, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Status Report

Why Are Mountaintops Cold? The Transition Of Surface Lapse Rate on Dry Planets

by Keith CowingNovember 20, 2023November 20, 2023

Understanding surface temperature is important for habitability. Recent work on Mars has found that the dependence of surface temperature on elevation (surface lapse rate) converges to zero in the limit […]

Tropical rainforest on Barro Colorado Island, Panama, near the site of the study. Credit: Marcos Guerra, STRI via NSF

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Habitable Zones, Plant Biology, Press Release

New Research Suggests Plants Might Be Able To Absorb More CO2 From Human Activities Than Previously Expected

by Keith CowingNovember 19, 2023November 19, 2023

New research published today in leading international journal Science Advances paints an uncharacteristically upbeat picture for the planet. This is because more realistic ecological modelling suggests the world’s plants may […]

Methane clathrate (white, ice-like material) under a rock from the seafloor of the northern Gulf of Mexico. Deposits such as these demonstrate that methane and other gases cross the seafloor and enter the ocean. Photo credit: NOAA

Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Press Release, ROVs/Submersibles/Diving, Water/Hycean Worlds & Oceanography

From Seafloor To Space: New Bacterial Proteins Shine Light On Climate and Astrobiology

by Keith CowingNovember 17, 2023November 17, 2023

Gigatons of greenhouse gas are trapped under the seafloor, and that’s a good thing. Around the coasts of the continents, where slopes sink down into the sea, tiny cages of […]

The sulfate poor waters of Lake Superior could provide insights on the biochemistry of Earth's early ocean. CREDIT Alexandra Phillips

Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Microbiology & Virology, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Research In Lake Superior Reveals How Sulfur Might Have Cycled In Earth’s Ancient Oceans

by Keith CowingNovember 17, 2023November 17, 2023

Geochemist Alexandra Phillips has sulfur on her mind. The yellow element is a vital macronutrient, and she’s trying to understand how it cycles through the environment. Specifically, she’s curious about […]

Outgoing thermal emission as a function of surface temperature. The dashed-dotted line is the classic runaway curve obtained with fully convective profiles, independently from the stellar radiation spectrum and internal flux. With self-consistent profiles, this function depends on the type of the host star and the internal flux ϕint. Dashed curves are obtained with Earth geothermal flux. For T-1 and ϕint < 0.01 Wm−2 , the runaway greenhouse can end without full vaporization of the ocean. Low-pressure liquidus, solidus and melting (melt fraction = 40%) temperatures are indicated for an Earth mantle composition. Surface pressure is 270 bars except in the blue area where Tsurf is below the critical temperature of H2O and psurf is given by the saturation vapor pressure of H2O. These curves are based on the profiles shown in Extended Data Figure 2 -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Lava / magma ocean / Volcanic Worlds, Status Report, Water/Hycean Worlds & Oceanography

A Cool Runaway Greenhouse Without Surface Magma Ocean

by Keith CowingNovember 17, 2023May 11, 2024

Water vapour atmospheres with content equivalent to the Earth’s oceans, resulting from impacts or a high insolation, were found to yield a surface magma ocean. This was, however, a consequence […]

Atmospheres, Climate, Weather

Deoxygenation Levels Similar To Today’s Played A Major Role In Marine Extinctions During Earth’s Major Past Climate Change Event

Massive 2022 Hunga Tonga-Hunga Ha’apai Eruption Reduced Earth’s Ozone Levels

Constraining Background N2 Inventories On Directly Imaged Terrestrial Exoplanets To Rule Out O2 False Positives

Methane And Water Found In The Atmosphere Of Exoplanet WASP-80 b

Under The Light Of A New Star: Evolution Of Planetary Atmospheres Through Protoplanetary Disc Dispersal And Boil-off

Why Are Mountaintops Cold? The Transition Of Surface Lapse Rate on Dry Planets

New Research Suggests Plants Might Be Able To Absorb More CO2 From Human Activities Than Previously Expected

From Seafloor To Space: New Bacterial Proteins Shine Light On Climate and Astrobiology

Research In Lake Superior Reveals How Sulfur Might Have Cycled In Earth’s Ancient Oceans

A Cool Runaway Greenhouse Without Surface Magma Ocean

ExoClock Unlocked: A Project To Increase Public Participation In Exoplanet Research

Galápagos Hydrothermal Vents Join Third 100 IUGS Geological Heritage Site Listing

Best Bulk Bennu (B3): Elemental Compositions Of Aggregate Samples From Asteroid Bennu K.

The Neptunian Ridge Through The Lens Of TESS

Sulfur Dioxide Sulfide (SSO2): The Elusive Isovalent Analogue of Sulfur Trioxide (SO3)