Seismic waves generated by earthquakes travel through Earth's solid iron inner core faster in the direction of the rotation axis than along the equator. UC Berkeley scientists created a core growth model to explain this. To fit seismic data, the model predicts that asymmetric growth of the core leads to crystal movement that preferentially aligns iron-nickel crystals north-south. The model implies that the core is only 0.5-1.5 billion years old, a fraction of Earth's age.
A study of two methods for reconstructing ancient temperatures has given climate researchers a better understanding of just how cold it was in Antarctica during the last ice age around 20,000 years ago.
Sea ice thickness is inferred by measuring the height of the ice above the water, and this measurement is distorted by snow weighing the ice floe down. Scientists adjust for this using a map of snow depth in the Arctic that is decades out of date. In the new study, researchers swapped this map for the results of a new computer model designed to estimate snow depth as it varies year to year.
New research shows that most extreme heat events are going to occur in the tropics rather than the poles.
It's strawberry season in many parts of the U.S, and supermarkets are teeming with these fresh heart-shaped treats. Although the bright red, juicy fruit can grow almost anywhere with lots of sunlight, production in some hot, dry regions is a challenge. Now, researchers reporting in ACS' Journal of Agricultural Food and Chemistry have identified five cultivars that are best suited for this climate, which could help farmers and consumers get the most fragrant, sweetest berries.
Ancient horse genomes reveal the timing and extent of dispersals across the Bering Land Bridge.
An analysis of sediment cores from the Bering Sea has revealed a recurring relationship between warmer climates and abrupt episodes of low-oxygen "dead zones" in the subarctic North Pacific Ocean over the past 1.2 million years. The findings provide crucial information for understanding the causes of low oxygen or "hypoxia" in the North Pacific and for predicting the occurrence of hypoxic conditions in the future.
Aerosol reductions that would take place as countries meet climate goals could contribute to global cooling and prevent more than one million annual premature deaths over a decade, according to a new study from the University of California San Diego.
Ozone depletion following the Toba eruption around 74,000 years ago compounded the ensuing volcanic winter and caused a human population bottleneck.
Researchers have identified the key factors that influence a vital pattern of ocean currents.