The inner core region of hurricanes harbors complex dynamical features, including small-scale clouds characterized by finger-like appearances pointing toward the hurricane eye. These features have been frequently observed in intense hurricanes. However, many basic aspects of these features remain unknown, particularly regarding what controls their occurrence, location, and spatial distribution. The authors conducted a numerical simulation with a very fine (about 100 m) horizontal grid spacing to investigate the nature of these features. Their results reveal a mechanism which explains several key characteristics of these features. Read More…
Assessing the impact of anthropogenic climate changes on tropical cyclone activity is of notable scientific and public interest. Since 1980, human-made aerosol emissions have decreased in Europe and the U.S. but increased in China and India. This study used SPEAR, a climate model developed at GFDL, to explore how regional aerosol changes affect global tropical cyclones. Read More…
Despite being the second-smallest ocean on Earth, the Southern Ocean plays an outsized role in absorbing heat and carbon generated from human activities, accounting for over 40% of the planet’s oceanic carbon uptake and 67%–98% of the global ocean heat uptake. As the climate warms, however, changes to the Southern Ocean’s circulation – caused by stronger, more southerly winds and increased meltwater from the Antarctic ice sheet – could affect its heat and carbon absorption abilities, which in turn would have significant consequences for global temperatures and sea level rise. Read More…
The occurrence of extreme weather events, such as heatwaves, droughts, and floods, has increased substantially since the pre-industrial period, but this trend has large regional variations. An important driver of the regional climate variability is the zonally asymmetric atmospheric circulation, or stationary waves, forced by the zonal asymmetries in the Earth’s surface such as the land-sea thermal contrast and elevated terrain (e.g., hills and mountains). Read More…
The Northwest Atlantic Shelf, from the coasts of North Carolina and Virginia to the Gulf of Maine to Newfoundland, has warmed more rapidly than almost any other part of the ocean in the last two decades. This warming has had severe impacts on marine ecosystems and coastal communities. Understanding the drivers of this warming and predicting whether it will continue is thus important for mitigating or adapting to future impacts. Read More…
Tropical Cyclones (TC) hitting Western Europe are not as rare as one might think. Approximately 10% of Atlantic TCs have made landfall in Europe in the past four decades, about one European landfall per year. Understanding and projecting TC frequency change is especially challenging in certain coastal regions with lower TC activity yet high exposure, and a relatively short duration of reliable observed records – such as Western Europe. Read More…
Large, damaging wildfires are becoming a common occurrence in Canada, the Pacific Northwest, and California. Five of the most destructive wildfire seasons of the last half-century have occurred in the past seven years. These wildfires can cause significant air pollution: burning biomass emits hundreds of reactive gases, including nitrogen oxides, carbon monoxide, ammonia, and an array of volatile organic compounds. Read More…
Nitrogen fertilizer usage and cultivation-induced biological nitrogen fixation help feed nearly half the global population. These practices, in addition to fossil fuel burning for energy production, have increased reactive nitrogen losses to the environment, causing a cascade of negative impacts on the ecosystem and human health. Nitrogen emissions to the atmosphere have contributed to acid rain, air pollution, stratospheric ozone depletion, and the radiative forcing underlying climate change. Nitrogen fluxes from lands have also impaired freshwater quality and contributed to coastal eutrophication, hypoxia, and harmful algal blooms, putting aquatic resources and the communities that depend upon them at risk. Read More…
Sea level rise (SLR) is one of the most severe consequences of a warming climate, causing dangerous flooding and threatening lives and infrastructure in low-lying coastal regions. This study investigated the potential physical drivers responsible for the observed acceleration of SLR after 2010 along the U.S. Southeast Coast. Using observations and climate models, the authors show that the rapid increase in the rate of SLR along the Southeast Coast after 2010 is due in part to multidecadal buoyancy-driven Atlantic meridional overturning circulation (AMOC) variations, along with heat transport convergence from wind-driven ocean circulation changes. Read More…
Recent studies indicate that virtually all global climate models have difficulty simulating observed sea surface temperature (SST) trend patterns over the past four decades. Models produce enhanced warming in the eastern Equatorial Pacific (EPAC) and Southern Ocean (SO) warming, while observations show intensified warming in the Indo-Pacific Warm Pool (IPWP) and slight cooling in the eastern EPAC and SO. Read More…
