Phys.org August 14, 2024 The strength and variability of the Southern Ocean carbon sink is a significant source of uncertainty in the global carbon budget. One barrier to reconciling observations and models is understanding how synoptic weather patterns modulate air-sea carbon exchange. An international team of researchers (USA – Monterey Bay Aquarium Research Institute, NCAR, Pacific Marine Environmental Laboratory, University of Arizona, Canada, South Africa) identified and tracked storms using atmospheric sea level pressure fields from reanalysis data to assess the role that storms play in driving air-sea CO2 exchange. They examined the main drivers of CO2 fluxes under storm […]
Category Archives: Climatology
New study unveils 16,000 years of climate history in the tropical Andes
Phys.org August 12, 2024 Understanding tropical South America’s climate history can provide valuable insight into the water cycle, ecosystems, and future climate change, yet past temperature changes are not well-known. An international team of researchers (USA – Brown University, Florida Institute of Technology, the Netherlands) reconstructed temperature and rainfall since ~16,800 y ago in the tropical Andes Mountains. In addition to warming driven by rising atmospheric CO2 concentrations, they observed rapid temperature changes linked to changes in the deep ocean circulation. Their findings suggested that Amazonia’s ecosystems may be challenged by rapid temperature changes superposed on warming from sharply increasing […]
Hidden players in climate change: How microscopic proteins could shape our future
Phys.org August, 1, 2024 Extremes in the magnitude and frequency of temperature changes are increasing across the planet, raising questions as to how the biosphere will respond. An international team of researchers (USA – Duke University, University of North Carolina, Germany) examined mechanisms of adaptation to temperature in the fungus Ashbya gossypii. They found that control of the nuclear division cycle and polarized morphogenesis, both critical processes for fungal growth, were temperature sensitive and varied among the isolates. The phenotypes were associated with naturally varying sequences of an RNA-binding protein called Whi3 which regulated both nuclear division and polarized growth. […]
New tipping point discovered beneath the Antarctic ice sheet
Phys.org June 25, 2024 Recently published studies of the complex hydrography of grounding zones suggest that warm ocean water can intrude large distances beneath the ice sheet, with dramatic consequences for ice dynamics. Researchers in the UK developed a model to capture the feedback between intruded ocean water, the melting it induces and the resulting changes in ice geometry showing a sensitive dependence of the grounding-zone dynamics on this feedback: as the grounding zone widens in response to melting, both temperature and flow velocity in the region increase, further enhancing melting. They found that increases in ocean temperature could lead […]
Scientists suggest causes behind one of the most significant climate catastrophes
Phys.org June 17, 2024 Anoxic events are prolonged periods where large expanses of the Earth’s oceans are depleted of dissolved oxygen, which creates toxic waters and leads to mass extinction and habitat loss. The cause of this anoxic event which lasted >500,000 years has been a source of debate among experts. Researchers in the UK used basin sedimentary mercury (Hg) concentrations to determine the timing of volcanism, and neodymium (Nd) and strontium (Sr) isotopes for sedimentary provenance. High Hg concentrations compared to Northern Hemisphere records, and a shift to radiogenic Nd isotopes, indicated Kerguelen LIP volcanic activity and plateau uplift […]
Researcher: Climate models can run for months on supercomputers—but my new algorithm can make them ten times faster
Phys.org May 4, 2024 Marine and terrestrial biogeochemical models are key components of the Earth System Models (ESMs) used to project future environmental changes, but their slow adjustment time also hinders effective use of ESMs because of the enormous computational resources required to integrate them to a pre-industrial equilibrium. Researchers in the UK developed a process based on “sequence acceleration” to accelerate equilibration of state-of-the-art marine biogeochemical models by over an order of magnitude. The technique could be applied in a “black box” fashion to existing models. Even under the challenging spin-up protocols used for Intergovernmental Panel on Climate Change […]
Long-term satellite observations show climatological characteristics of isolated deep convection over the Tibetan Plateau
EurekAlert April 10, 2024 Researchers in China investigated isolated deep convections (IDCs), which have a smaller spatial and temporal size than mesoscale convective systems (MCSs), over the TP in the rainy season during 2001–2020. They showed that IDCs mainly concentrated over the southern Tibetan plateau (TP). The larger IDC had intense precipitation contributing 20 %–30 % to total precipitation, with a larger percentage in July and August than in June and September. IDCs contribute more to both total precipitation and extreme precipitation over the TP compared to the surrounding plain regions. IDCs over the TP account for a larger fraction […]
Earth’s ‘third pole’ and its role in global climate
Phys.org August 25, 2023 Researchers in China reviewed recent advances in research regarding land–atmosphere coupling processes over the Tibetan Plate (TP) and concluded that climate warming has caused glacier retreat, permafrost degradation, and a general increase in vegetation density, while climate wetting has led to a significant increase in the number of major lakes, primarily through increased precipitation. The TP drives surface pollutants to the upper troposphere in an Asian summer monsoon (ASM) anticyclone circulation before spreading to the lower stratosphere. The thermal forcing of the TP plays an essential role in the ASM. TP forcing can modulate hemispheric-scale atmospheric […]
Researchers take aim at weather forecasters’ biggest blind spot
Phys.org August 29, 2023 A team of researchers in the US (Stevens Institute of Technology, NOAA) evaluated spatiotemporal variability of deterministic and probabilistic precipitation nowcasting models’ performance over the greater New York City area. They assessed five deterministic and two probabilistic nowcasting methods using Multi-Radar Multi-Sensor data from 2014 to 2022. Three lead times of 2, 4 and 6 h were considered. LINDA-P had the best average Pearson’s correlation of 0.87 at the first step and 0.47 at the last one and the longest 80 min average decorrelation times. Its Mean Absolute Error (MAE) was four times lower in winter […]
Effect of volcanic eruptions significantly underestimated in climate projections
Science Daily June 23, 2023 Standard climate projections, as in Intergovernmental Panel on Climate Change Sixth Assessment Report, assume that explosive volcanic activity over 2015–2100 are of the same level as the 1850–2014 period. Researchers in the UK used the latest ice-core and satellite records to design stochastic eruption scenarios, to show that there is a 95% probability that explosive eruptions could emit more sulfur dioxide (SO2) into the stratosphere over 2015–2100 than current standard climate projections (i.e., ScenarioMIP). Their simulations using the UK Earth System Model with interactive stratospheric aerosols showed that for a median future eruption scenario, the […]