In 2021, the cover of the science magazine Science has a lot of new discoveries about Earth science, from Jupiter's atmosphere to Martian flash floods, from warming in the Arctic to falling groundwater levels. These new discoveries help us uncover the Earth and explore the universe.
Juno spacecraft data probe the depth and structure of Jupiter's Great Red Spot
VOLUME 374| ISSUE 6570|19 NOV 2021
Jupiter's atmosphere is filled with massive storms and swirling wind bands, including a 16,000-kilometer-wide Great Red Spot (GRS) powerful enough to engulf the entire planet. Scott Bolton's team and Marzia Parisi's team used microwave and gravity measurements from juno's spacecraft to describe atmospheric vortexes dominated by Jupiter GRS, respectively. Although GRS does not exceed 500 km deep in the atmosphere, the surrounding jets can extend up to 3000 ka. Studies of its vertical structure also suggest a link between Jupiter's interior and deep atmosphere; storms can cause fluctuations in the planet's gravitational field.
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Bolton, S. J., Levin, S. M., Guillot, T., Li, C., Kaspi, Y., Orton, G., Wong, M. H., Oyafuso, F., Allison, M., Arballo, J., Atreya, S., Becker, H. N., Bloxham, J., Brown, S. T., Fletcher, L. N., Galanti, E., Gulkis, S., Janssen, M., Ingersoll, A., Lunine, J. L., Misra, S., Steffes, P., Stevenson, D., Waite, J. H., Yadav, R. K., and Zhang, Z., 2021, Microwave observations reveal the deep extent and structure of Jupiter’s atmospheric vortices: Science, v. 374, no. 6570, p. 968-972.
Parisi, M., Kaspi, Y., Galanti, E., Durante, D., Bolton, S. J., Levin, S. M., Buccino, D. R., Fletcher, L. N., Folkner, W. M., Guillot, T., Helled, R., Iess, L., Li, C., Oudrhiri, K., and Wong, M. H., 2021, The depth of Jupiter’s Great Red Spot constrained by Juno gravity overflights: Science, v. 374, no. 6570, p. 964-968.
Mars has experienced flash floods
VOLUME 374| ISSUE 6568|5 NOV 2021
The Perseverance rover chose to land at Jezero Crater, which has remnants of ancient lakes, in February 2021. Using the Mastcam-Z and Demote Micro-Imager (RMI) instruments, the rover imaged the rock formations and sediment layers around the landing site and discovered the hydrological evolution of craters. Studies have shown evidence of the presence of sloping formations in outcrops that are moving from stable lake environments to high-energy short-term rivers; large boulders in the uppermost fan-shaped formations represent the sedimentation of intermittent high-energy floods; and the smallest material at the bottom of the delta may be the best choice for future studies of Martian organic matter and biocharacters.
Mangold, N., Gupta, S., Gasnault, O., Dromart, G., Tarnas, J. D., Sholes, S. F., Horgan, B., Quantin-Nataf, C., Brown, A. J., Mouélic, S. L., Yingst, R. A., Bell, J. F., Beyssac, O., Bosak, T., Calef, F., Ehlmann, B. L., Farley, K. A., Grotzinger, J. P., Hickman-Lewis, K., Holm-Alwmark, S., Kah, L. C., Martinez-Frias, J., McLennan, S. M., Maurice, S., Nu ez, J. I., Ollila, A. M., Pilleri, P., Rice, J. W., Rice, M., Simon, J. I., Shuster, D. L., Stack, K. M., Sun, V. Z., Treiman, A. H., Weiss, B. P., Wiens, R. C., Williams, A. J., Williams, N. R., and Williford, K. H., 2021, Perseverance rover reveals an ancient delta-lake system and flood deposits at Jezero crater, Mars: Science, v. 374, no. 6568, p. 711-717.
Mysterious ice plumes predict deadly storms
VOLUME 373| ISSUE 6560|10 SEP 2021
After Hurricane Ada swept through the United States, super-monomer thunderstorms and tornadoes followed, causing great damage. Previous research has shown that when a cloudy cloud of ice-water vapor rolls over a strong thunderstorm, a tornado or hail will subsequently hit the surface. We always capture these plumes in satellite imagery more than 30 minutes before bad weather reaches the ground. This study attempts to use models to explain the mechanisms of these plumes. Through computer simulations of idealized superunibody thunderstorms, O'Neill et al. found that winds from the upper atmosphere, when hovering at the top of the storm, provoked water vapor and water currents that would shoot into the stratosphere to form a barrier that deflected the high-altitude airflow. This creates a water jump downstream of the storm at the top of the troposphere. The latter, once formed, would forcefully inject water vapor deep into the stratosphere at speeds of more than 240 miles per hour, affecting the mass and quantity of sunlight reaching Earth. It is worth mentioning that Leonardo da Vinci recorded this phenomenon five hundred years ago.
O’Neill, M. E., Orf, L., Heymsfield, G. M., and Halbert, K., 2021, Hydraulic jump dynamics above supercell thunderstorms: Science, v. 373, no. 6560, p. 1248-1251.
Warming in the Arctic leads to colder winters
VOLUME 373| ISSUE 6559|3 SEP 2021
Global warming has long contradicted extremely cold weather in the United States and northern Eurasia, which has also become an excuse for some to use not to reduce emissions. Satellite records over the past four decades show that rising global temperatures have caused the Arctic summer sea ice to shrink, bringing about significant warming. The melting of ice in the Barents And Kara Sea has led to increased snowfall over Siberia, which together have amplified the temperature difference between the east and west ends of Eurasia, weakening the polar vortex and leading to more extreme cooling events. Excess energy extended the vortex winds in the stratosphere over the Arctic, causing extremely cold weather to flow to the United States. Arguably, there is a real link between the rapid warming of the Arctic and its effects (i.e., the loss of sea ice and the increase in snowfall cover in Eurasia) with stratospheric vortex disruption and increased frequency of extreme winter weather in the mid-latitudes. The study could extend the advance warning time for extreme cold weather in Asia, Canada and the United States.
Cohen, J., Agel, L., Barlow, M., Garfinkel, C. I., and White, I., 2021, Linking Arctic variability and change with extreme winter weather in the United States: Science, v. 373, no. 6559, p. 1116-1121.
Through isotopes, we peek into the life of a mammoth
VOLUME 373| ISSUE 6556|13 AUG 2021
In the Pleistocene, mammoths entered North America from Northern Europe and Asia, via Russia. Exactly how far a mammoth can go has become a concern. A study led by Wooller at the University of Alaska used the 1.8m-year-old mammoth's fangs about 17,100 years ago as a carrier to collect data on 400,000 points along the length of the ivory using oxygen and strontium isotopes to piece together the male mammoth's 28-year-old life. Using the principle that different regions have different isotopic characteristics, the researchers collected the teeth of small rodents from around the world to make an Alaskan isotope map. Comparison shows that the mammoth's early trek back and forth between the Yukon River valley and the alaska interior was quite regular; by the age of 15, mutations in isotopic data suggested that adult elephants might have left the herd and traveled randomly; and in the last years of its life, the mammoth had been moving in small areas off the northern coast of Alaska. The high content of nitrogen at the base of ivory also indicates its starvation and death.
Wooller, M. J., Bataille, C., Druckenmiller, P., Erickson, G. M., Groves, P., Haubenstock, N., Howe, T., Irrgeher, J., Mann, D., Moon, K., Potter, B. A., Prohaska, T., Rasic, J., Reuther, J., Shapiro, B., Spaleta, K. J., and Willis, A. D., 2021, Lifetime mobility of an Arctic woolly mammoth: Science, v. 373, no. 6556, p. 806-808.
Use Martian earthquakes to determine the structure of the Earth's crust on Mars
VOLUME 373| ISSUE 6553|23 JUL 2021
A planet's crust bears witness to the history of planet formation and evolution. The researchers came to conclusions about the internal structure of Mars by analyzing Mars seismic data recorded on the InSight lander over the past two years. Brigitte Knapmeyer-Endrun et al. used Martian seismic and environmental seismic noise to image the structure of the Martian crust beneath the InSight landing site, arguing that the Martian crust is a multilayer structure with 2 or 3 interfaces, including a crust 24 to 72 km thick and a 500 km deep lithosphere (the latter is the masterpiece of Amir Khan et al.). Simon St Hler et al. discovered through seismic wave reflections at the nuclear mantle boundary that the core of Mars is liquid and its radius may be around 1830 km. Contrary to Earth, Mars appears to lack a lower mantle and has only one layer of rock. These three studies provide important constraints on the current structure of Mars and provide key evidence for human understanding of the formation and evolution of the planet.
Khan, A., Ceylan, S., Driel, M. v., Giardini, D., Lognonné, P., Samuel, H., Schmerr, N. C., St hler, S. C., Duran, A. C., Huang, Q., Kim, D., Broquet, A., Charalambous, C., Clinton, J. F., Davis, P. M., Drilleau, M., Karakostas, F., Lekic, V., McLennan, S. M., Maguire, R. R., Michaut, C., Panning, M. P., Pike, W. T., Pinot, B., Plasman, M., Scholz, J.-R., Widmer-Schnidrig, R., Spohn, T., Smrekar, S. E., and Banerdt, W. B., 2021, Upper mantle structure of Mars from InSight seismic data: Science, v. 373, no. 6553, p. 434-438.
Knapmeyer-Endrun, B., Panning, M. P., Bissig, F., Joshi, R., Khan, A., Kim, D., Leki , V., Tauzin, B., Tharimena, S., Plasman, M., Compaire, N., Garcia, R. F., Margerin, L., Schimmel, M., Stutzmann, ., Schmerr, N., Bozda , E., Plesa, A.-C., Wieczorek, M. A., Broquet, A., Antonangeli, D., McLennan, S. M., Samuel, H., Michaut, C., Pan, L., Smrekar, S. E., Johnson, C. L., Brinkman, N., Mittelholz, A., Rivoldini, A., Davis, P. M., Lognonné, P., Pinot, B., Scholz, J.-R., St hler, S., Knapmeyer, M., Driel, M. v., Giardini, D., and Banerdt, W. B., 2021, Thickness and structure of the martian crust from InSight seismic data: Science, v. 373, no. 6553, p. 438-443.
St hler, S. C., Khan, A., Banerdt, W. B., Lognonné, P., Giardini, D., Ceylan, S., Drilleau, M., Duran, A. C., Garcia, R. F., Huang, Q., Kim, D., Lekic, V., Samuel, H., Schimmel, M., Schmerr, N., Sollberger, D., Stutzmann, ., Xu, Z., Antonangeli, D., Charalambous, C., Davis, P. M., Irving, J. C. E., Kawamura, T., Knapmeyer, M., Maguire, R., Marusiak, A. G., Panning, M. P., Perrin, C., Plesa, A.-C., Rivoldini, A., Schmelzbach, C., Zenh usern, G., Beucler, ., Clinton, J., Dahmen, N., Driel, M. v., Gudkova, T., Horleston, A., Pike, W. T., Plasman, M., and Smrekar, S. E., 2021, Seismic detection of the martian core: Science, v. 373, no. 6553, p. 443-448.
The Ramla people, older than the Neanderthals
VOLUME 372| ISSUE 6549|25 JUN 2021
The 140,000-120,000-year-old Nesher Ramla Homo ancient human fauna found in the open-air site of Nesher Ramla in Israel represents the last surviving population of Middle Pleistocene humans. They combine neanderthal and other ancient human features, with instrument-making techniques that exist only in Homo sapiens and Neanderthals. This ancient race is thought to have been one of the last surviving groups of Pleistocene humans in Southwest Asia, Africa and Europe.
Hershkovitz, I., May, H., Sarig, R., Pokhojaev, A., Grimaud-Hervé, D., Bruner, E., Fornai, C., Quam, R., Arsuaga, J. L., Krenn, V. A., Martinón-Torres, M., Castro, J. M. B. d., Martín-Francés, L., Slon, V., Albessard-Ball, L., Vialet, A., Schüler, T., Manzi, G., Profico, A., Vincenzo, F. D., Weber, G. W., and Zaidner, Y., 2021, A Middle Pleistocene Homo from Nesher Ramla, Israel: Science, v. 372, no. 6549, p. 1424-1428.
River things
VOLUME 372| ISSUE 6543|14 MAY 2021
As one of the most silted rivers in the world, the Gosi Carries a large amount of sediment from the Himalayas upstream each year. Near Kusaha, India, the river enters the foothill plain, which allows the large amount of clastic material carried by the river to settle rapidly. As a result, over time, the river's carrying capacity weakens and it is diverted to find a more suitable route point. As this model is gradually mastered and successfully predicted by humans, the simulation results become unreliable due to the construction of flood control embankments downstream, deforestation upstream, etc., and people continue to suffer from river flooding disasters again and again.
Falling groundwater levels threaten global well levels
VOLUME 372| ISSUE 6540|23 APRIL 2021
Groundwater provides nearly half of the water for agricultural irrigation and provides most of the drinking water for billions of people. Therefore, the security of this resource is essential. Jasechko and Perrone studied data from about 39 million oil wells in 40 countries around the world to investigate their vulnerability to falling water levels. The survey found that in some areas that are experiencing groundwater declines, there are no plans to build deep-water wells. This contradiction between the need for production and survival and backward construction poses a risk to people who depend on well water for a living.
Famiglietti, J. S., and Ferguson, G., 2021, The hidden crisis beneath our feet: Science, v. 372, no. 6540, p. 344-345.
Jasechko, S., and Perrone, D., 2021, Global groundwater wells at risk of running dry: Science, v. 372, no. 6540, p. 418-421.
In the late Cretaceous period, there were 2.5 billion Tyrannosaurus rex
VOLUME 373| ISSUE 6553|16 APRIL 2021
Assessing the abundance of a species can help reveal its ecology, evolution, etc. However, for animals that have been extinct for a long time, this is not an easy task. Some researchers used the relationship between the weight of extant animals and the density of the population to estimate the species abundance of T. rex. They found that nearly 20,000 Tyrannosaurus rexes existed simultaneously at any time they were active on Earth; they lasted for about 127,000 generations, so the total number of T. rex that once appeared on Earth was 2.5 billion.
Marshall, C. R., Latorre, D. V., Wilson, C. J., Frank, T. M., Magoulick, K. M., Zimmt, J. B., and Poust, A. W., 2021, Absolute abundance and preservation rate of Tyrannosaurus rex: Science, v. 372, no. 6539, p. 284-287.
An evolutionary attempt at cretaceous sharks – to become plankton?
VOLUME 371| ISSUE 6535|19 MAR 2021
Modern sharks dominate marine ecosystems around the world, but have little morphological diversity and are mostly streamlined carnivores. Vullo et al. found fossil remains of a new manta ray-like shark called Aquilolamna milarcae in northern Mexico, dating back about 93 million years (late Cretaceous). This shark exhibits a number of manta ray-like features, such as slender pectoral fins and large mouths suitable for filtering feeding, as well as the special tail fins and body morphology of other types of sharks. This previously unknown body plan represents an unexpected evolutionary experiment in shark underwater flight, predates the rise of manta rays and manta rays more than 30 million years ago, and suggests that the wing-like pectoral fins evolved independently in two distantly relative branches of filter-feeding plate gills. This newly described highly specialized group of long-winged sharks (Aquilolamnidae) shows a type of ecological morphology similar to aquatic life and may have occupied niches occupied by white sharks and other short-tailed sharks in the oceans of the Late Mesozoic Period.
Vullo, R., Frey, E., Ifrim, C., González, M. A. G., Stinnesbeck, E. S., and Stinnesbeck, W., 2021, Manta-like planktivorous sharks in Late Cretaceous oceans: Science, v. 371, no. 6535, p. 1253-1256.
Editor: Wan Peng
Editor: Xu Hongxi
Proofreader: Qin Huaqing Jiang Shumin