Science Daily February 16, 2023 The objective of EPICA [European Project for Ice Coring in Antarctica] is to look back 1.5 million years into the past and obtain data on the development of temperature, the composition of the atmosphere and the carbon cycle. A depth of around 2700 meters must be reached in the Antarctic ice sheet and an ice core recovered which they plan to accomplish by 2025. In the 1.5-million-year-old ice, 15,000 to 20,000 years of climate history are compressed into just one meter of ice core, which places completely new demands on ice core analyzes. Researchers in […]
Category Archives: Climatology
What drives the recent decline of East Asian dust activity?
Phys.org December 21, 2022 Dust entrained into the atmosphere serves as a major aerosol type, exerting effects on weather and climate system via aerosol-radiation-cloud interactions and delivering nutrients from continents to other continents and oceans. Using a physically-based dust emission model, an international team of researchers (China, Germany, USA – Texas A&M University) has shown that the weakening of surface wind and the increasing of vegetation cover and soil moisture have all contributed to the decline in dust activity during 2001 to 2017. The relative contributions of these three factors to the dust emission reduction during 2010–2017 relative to 2001 […]
Cloud study demystifies impact of aerosols
Science Daily August 1, 2022 Aerosol–cloud interactions have a potentially large impact on climate. The impacts derived from climate models are poorly constrained by observations because retrieving robust large-scale signals of aerosol–cloud interactions is frequently hampered by the considerable noise associated with meteorological co-variability. An international team of researchers (UK, Switzerland, Germany, USA – NASA) disentangled significant signals from the noise of meteorological co-variability using a satellite-based machine-learning approach. Their analysis showed that aerosols from the 2014 Holuhraun effusive eruption in Iceland increased cloud cover by approximately 10%, and this appears to be the leading cause of climate forcing, rather […]
Predicting rainfall futures
Phys.org June 16, 2022 According to an international team of researchers (UK, USA – Caltech, Germany, Switzerland) the basis around which climate models have been built over the last 30 years misses some fundamental physics that we now know is essential for reliable predictions. The answers exist but a huge joint international investment in resources, expertise, and infrastructure—amounting to an estimated $250 million annually—is urgently needed to develop much more advanced climate models. The current 100 kilometer-scale global climate models should be changed to 1 kilometer-scale models. At these scales, the complex physics of rain-bearing systems is properly represented with […]
A cloudless future? The mystery at the heart of climate forecasts
Science Daily May 31, 2022 Analyses of global climate models consistently show that clouds constitute the biggest source of uncertainty and instability. But they occur on a length- and timescale that today’s models can’t come close to reproducing. Therefore, they included in models through a variety of approximations. A team of researchers in the US (UC Irvine, Lawrence Livermore National Laboratory, University of Washington, industry) is working to fix this glaring gap by breaking the climate modeling problem into two parts: a coarse-grained, lower-resolution (100km) planetary model and many small patches with 100 to 200 meter resolution. They developed a […]
Release of two new datasets related to climate in Central Asia
Phys.org May 23, 2022 Researchers in China have derived a high-resolution (9 km) climate projection dataset over Central Asia (HCPD-CA) from dynamically downscaled results based on multiple bias-corrected global climate models. It contains four geostatic variables and 10 meteorological elements that are widely used to drive ecological and hydrological models. The reference and future periods are 1986–2005 and 2031–2050, respectively. The carbon emission scenario is Representative Concentration Pathway (RCP) 4.5. The evaluation showed that the data product has good quality in describing the climatology of all the elements in CA despite some systematic biases. Main features of projected climate changes over […]
Insights narrow the gap between large-scale atmospheric models and microscale features of atmospheric winds
Phys.org April 26, 2022 Modeling anomalies referred to as grey zone, arise when the model resolution approximates the length scale of turbulence features while modeling the atmosphere. An international team of researchers (USA – Notre Dame, Saudi Arabia) leveraged a new set of one-way nested, full-physics multiscale numerical experiments to quantify the magnitude of the errors introduced at gray zone resolutions in a real-case application. The new set of experiments conducted in Saudi Arabia spanned a wide range of scales and strategies to suppress resolved convection at gray zone resolutions. Detailed analyses of their experiments showed that (i) grid-dependent convective […]
Student’s research upends understanding of upper atmospheric wind
Phys.org November 10, 2021 Researchers at the University of Alaska analyzed ground-based remote sensing measurements of thermospheric neutral winds above Alaska, at 240 km altitude to study how space weather affects the well-known large-scale flow that carries winds from the sunlit dayside of the Earth across the polar cap into the night side. This flow feature is typically expected to emerge from the polar cap in the midnight sector and continue blowing equatorward well into sub-auroral latitudes. However, their data showed instances in which the equatorward flow instead stalls over Alaska in an unexpectedly abrupt manner. They found this most […]
Weather balloon data shows troposphere getting thicker, pushing tropopause higher over past 40 years
Phys.org November 8, 2021 Tropopause height (H) is a sensitive diagnostic for anthropogenic climate change. Previous studies showed increases in H over 1980–2000 but were inconsistent in projecting H trends after 2000. While H generally responds to temperature changes in the troposphere and stratosphere, the relative importance of these two contributions is uncertain. An international team of researchers (China, Canada, USA – NCAR, Boulder CO, Austria) used radiosonde balloon observations in the Northern Hemisphere (NH) over 20°N to 80°N to reveal a continuous rise of H over 1980–2020. Over 2001–2020, H increases at 50 to 60 m/decade, which is comparable […]
Earth’s orbit affects millennial climate variability
Phys.org November 2, 2021 The varying magnitude of millennial climate variability (MCV) was linked to orbitally paced glacial cycles over the past 800 kyr. The scarcity of a long-term integration of high-resolution continental and marine records hampers our understanding of the evolution and dynamics of MCV before the mid-Pleistocene transition. An international team of researchers (China, USA – Columbia University, Brown University, Switzerland, UK) has synthesized four centennial-resolved elemental time series, which they interpret as proxies for MCV, from North Atlantic, Iberian margin, Balkan Peninsula (Lake Ohrid) and Chinese Loess Plateau. The proxy records reveal that MCV was pervasive and persistent […]