(Press-News.org) When clouds meet clear skies, cloud droplets evaporate as they mix with dry air. A new study involving researchers from the University of Gothenburg has succeeded in capturing what happens in a model. Ultimately, this could lead to more accurate climate modeling in the future.
The clouds in the sky have a significant impact on our climate. Not only do they produce precipitation and provide shade from the sun, they also act as large reflectors that prevent the radiation of heat from the Earth – commonly known as the greenhouse effect.
“Although clouds have been studied for a long time, they are one of the biggest sources of uncertainty in climate models,” explains Bernhard Mehlig, Professor of Complex Systems at the University of Gothenburg. “This is because there are so many factors that determine how the clouds affect radiation. And the turbulence in the atmosphere means that everything is in constant motion. This makes things even more complicated.”
Focusing on the cloud edge
A scientific article in Physical Review Letters presents a new statistical model that describes how the number of water droplets, their sizes and the water vapour interact at the turbulent cloud edge. The distribution of water droplets is important because it affects how clouds reflect radiation.
“The model describes how the droplets shrink and grow at the cloud edge when turbulence mixes in drier air,” adds Johan Fries, a former doctoral student in physics and co-author of the study.
The researchers have identified the most important parameters, and have built their model accordingly. In brief, the model takes into account the laws of thermodynamics and the turbulent motion of the droplets. The model corresponds well with earlier numerical computer simulations, and explains their results.
The importance of evaporation
“But we’re still a long way from the finish line,” continues Professor Mehlig. “Our model is currently able to describe what is happening in one cubic metre of cloud. Say, fifteen years ago it was only one cubic centimetre, so we’re making progress.”
When policymakers discuss climate change, great importance is attached to IPCC climate models. However, according to the IPCC, the microphysical properties of clouds are among the least understood factors in climate science.
“Moreover, the evaporation of droplets is an important process, not only in the context of atmospheric clouds, but also within the field of infectious medicine. Tiny droplets that are produced when we sneeze can contain virus particles. If these droplets evaporate, the virus particles can remain in the air and infect others.”
Professor Mehlig has also co-authored another study that describes how solid particles, such as ice crystals, move within clouds.
“The ice crystals and the water droplets affect each other. But we don’t yet know how.”
END
New cloud model could help with climate research
2024-02-21
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
Unravelling the genetic and environmental influences on trust
2024-02-21
Trust, a cornerstone of human interaction, has a significant genetic component, with around 33% of the variation between individuals attributed to our genes, according to new Australian research using data from twins and a meta-analysis of previous studies on the heritability of trust.
Successful relationships, economic transactions and social cohesion are all a matter of trust. Without trust, businesses collapse, political parties fail, and conflicts erupt, whether on a personal or international scale, resulting in broken hearts and lives lost.
“Higher levels of trust are associated with a range of social and economic benefits, ...
People who a eat healthy, plant-based diet are less likely to suffer with dangerous snoring
2024-02-21
People who eat a healthy, plant-based diet that is high in vegetables, fruit, whole grains and nuts are less likely to suffer with obstructive sleep apnoea (OSA), according to a study published today (Wednesday) in ERJ Open Research [1]. However, people eating an unhealthy plant-based diet, high in refined carbohydrates, sugary drinks, high-sugar and high-salt foods, are at a higher risk of OSA.
People with OSA often snore loudly, their breathing starts and stops during the night, and they may wake up several times. Not only does this cause tiredness, but it can also increase the risk of high blood pressure, stroke, heart disease and type 2 diabetes.
The new study ...
Angle-dependent holograms made possible by metasurfaces
2024-02-21
The expression "flawless from every angle" is commonly used to characterize a celebrity's appearance. This doesn't simply imply that they appear attractive from a specific viewpoint, but rather that their appeal remains consistent and appealing from various angles and perspectives. Recently, a research team from Pohang University of Science and Technology (POSTECH) has employed metasurface to fabricate angle-dependent holograms with multiple functions, capturing significant interest within ...
These tiny power converters run on vibrational energy
2024-02-21
University of California San Diego and CEA-Leti scientists have developed a ground-breaking piezoelectric-based DC-DC converter that unifies all power switches onto a single chip to increase power density. This new power topology, which extends beyond existing topologies, blends the advantages of piezoelectric converters with capacitive-based DC-DC converters.
The power converters the team developed are much smaller than the huge, bulky inductors currently used for this role. The devices could eventually be used for any type of DC-DC conversation, ...
Ochsner Health Hospitals accredited as Surgical Review Corporation Centers of Excellence
2024-02-21
NEW ORLEANS, La – Ochsner Medical Center – New Orleans achieved accreditation as a Center of Excellence in Robotic Surgery, and Ochsner Baptist – A Campus of Ochsner Medical Center, inclusive of Ochsner Medical Center and Ochsner Medical Complex- Clearview, received accreditation as a Center of Excellence in Continence Care for Women by SRC (Surgical Review Corporation). This accreditation recognizes Ochsner Health’s commitment to a high standard of quality patient care delivery and safety.
“Robotic ...
$2 million grant from The Roe Green Foundation catalyzes multidisciplinary research building in Uganda
2024-02-21
CLEVELAND--For the past 38 years, Case Western Reserve University (CWRU) and University Hospitals (UH) have worked closely with a variety of institutions in Uganda to advance medical research and education across a range of fields.
Their facilities have remained scattered across the campuses of local partners but now, the collaboration will have a permanent home.
A $2 million gift from The Roe Green Foundation, jointly awarded to CWRU and UH, will advance global health initiatives from each institution and establish a state-of-the-art research hub and gathering ...
SFU researchers develop AI that can understand light in photographs
2024-02-21
Despite significant progress in developing AI systems that can understand the physical world like humans do, researchers have struggled with modelling a certain aspect of our visual system: the perception of light.
“Determining the influence of light in a given photograph is a bit like trying to separate the ingredients out of an already baked cake.” explains Chris Careaga, a PhD student in the Computational Photography Lab at SFU. The task requires undoing the complicated interactions between light and surfaces in a scene. This problem is referred to as intrinsic decomposition, and has been ...
Minority ethnic NHS staff more likely to face workplace discrimination during pandemic than White colleagues
2024-02-21
Minority ethnic NHS staff were more likely to face workplace harassment, discrimination, and unavailability of personal protective equipment (PPE) than their White British colleagues during the pandemic, reveals research published online in the journal Occupational & Environmental Medicine.
Urgent action is needed to redress ongoing race inequalities in the health service, insist the researchers, who call for the inclusion of diversity and inclusion training in professional development, and the expansion of the NHS Workforce Race Equality Standard.
Staff from minority ethnic groups make up nearly ...
J-shaped curve apparent between dietary thiamine and worsening mental acuity
2024-02-21
There seems to be a J-shaped curve between dietary thiamine (vitamin B1) and worsening mental acuity among cognitively healthy older people, suggests research published in the open access journal General Psychiatry.
The sweet spot seems to be a daily intake of 0.68 mg, below which there is relatively little impact. But higher daily intake was strongly associated with cognitive decline, with the optimal maintenance dose 0.6 to less than 1 mg/day, the findings show.
Thiamine is an essential water-soluble B vitamin involved in energy metabolism and brain neurotransmitter activity. Good dietary sources include whole grains, fortified ...
Adopting healthy lifestyle strongly linked to lower irritable bowel syndrome risk
2024-02-21
Adopting a healthy lifestyle is strongly linked to a lower risk of irritable bowel syndrome or IBS for short, finds research published online in the journal Gut.
Of the big 5 healthy behaviours, not smoking, a high level of vigorous physical activity, and getting enough sleep were independently associated with keeping the condition at bay.
Characterised by abdominal pain, bloating, and abnormal bowel habit, IBS is thought to affect up to 1 in 10 people worldwide. Exactly what causes IBS isn’t fully understood, but disordered functioning of the gut–brain ...