A new study suggests Earth's subtropical low-cloud zones are shrinking, allowing more sunlight to reach the ocean and accelerating global warming. By combining satellite observations with climate models, researchers found strong evidence that decreased cloud cover is a consequence of rising CO2 levels, and not just natural variation. This positive feedback loop, where warming reduces clouds which then leads to more warming, could amplify the effects of climate change beyond current projections. The study highlights the importance of low clouds in regulating Earth's temperature and underscores the potential for even more rapid warming than previously anticipated.
Project Aardvark aims to revolutionize weather forecasting by using AI, specifically deep learning, to improve predictions. The project, a collaboration between the Alan Turing Institute and the UK Met Office, focuses on developing new nowcasting techniques for short-term, high-resolution forecasts, crucial for predicting severe weather events. This involves exploring a "physics-informed" AI approach that combines machine learning with existing weather models and physical principles to produce more accurate and reliable predictions, ultimately improving the safety and resilience of communities.
HN commenters are generally skeptical of the claims made in the article about revolutionizing weather prediction with AI. Several point out that weather modeling is already heavily reliant on complex physics simulations and incorporating machine learning has been an active area of research for years, not a novel concept. Some question the novelty of "Fourier Neural Operators" and suggest they might be overhyped. Others express concern that the focus seems to be solely on short-term, high-resolution prediction, neglecting the importance of longer-term forecasting. A few highlight the difficulty of evaluating these models due to the chaotic nature of weather and the limitations of existing metrics. Finally, some commenters express interest in the potential for improved short-term, localized predictions for specific applications.
Astronomers have detected incredibly fast winds, reaching speeds up to 10,000 mph (5 km/s), on the exoplanet HD 209458b. This hot Jupiter, already known for its evaporating atmosphere, has provided the first direct measurement of wind speeds on a planet outside our solar system. Researchers used high-resolution spectroscopy to observe carbon monoxide in the planet's atmosphere, tracking its movement with unprecedented precision and revealing these extreme supersonic winds blowing from the hot dayside to the cooler nightside. This breakthrough offers valuable insights into atmospheric dynamics on exoplanets and advances our understanding of planetary weather systems beyond our solar system.
HN commenters discuss the challenges and limitations of measuring wind speeds on exoplanets, particularly highlighting the indirect nature of the measurements and the assumptions involved. Some express skepticism, questioning the precision of such measurements given our current technology and understanding of exoplanetary atmospheres. Others are fascinated by the extreme conditions described and speculate about the implications for atmospheric dynamics and potential habitability. A few commenters point out the potential for future research with more advanced telescopes like the Extremely Large Telescope (ELT), hoping for more accurate and detailed data on exoplanetary atmospheres and weather patterns. There's also some technical discussion of the Doppler broadening technique used for these measurements and how it relates to atmospheric escape. Finally, some users question the newsworthiness, suggesting this is a relatively minor incremental advance in exoplanet research.
Researchers have demonstrated a method for using smartphones' GPS receivers to map disturbances in the Earth's ionosphere. By analyzing data from a dense network of GPS-equipped phones during a solar storm, they successfully imaged ionospheric variations and travelling ionospheric disturbances (TIDs), particularly over San Francisco. This crowdsourced approach, leveraging the ubiquitous nature of smartphones, offers a cost-effective and globally distributed sensor network for monitoring space weather events and improving the accuracy of ionospheric models, which are crucial for technologies like navigation and communication.
HN users discuss the potential impact and feasibility of using smartphones to map the ionosphere. Some express skepticism about the accuracy and coverage achievable with consumer-grade hardware, particularly regarding the ability to measure electron density effectively. Others are more optimistic, highlighting the potential for a vast, distributed sensor network, particularly for studying transient ionospheric phenomena and improving GPS accuracy. Concerns about battery drain and data usage are raised, along with questions about the calibration and validation of the smartphone measurements. The discussion also touches on the technical challenges of separating ionospheric effects from other signal variations and the need for robust signal processing techniques. Several commenters express interest in participating in such a project, while others point to existing research in this area, including the use of software-defined radios.
Summary of Comments ( 51 )
https://news.ycombinator.com/item?id=43592756
Hacker News users discuss the study's implications and methodology. Several express concern about the potential for a positive feedback loop, where warming reduces cloud cover, leading to further warming. Some question the reliability of satellite data used in the research, citing potential biases and the short timescale of observation. Others highlight the complexity of cloud behavior and the difficulty of modeling it accurately, suggesting the need for more research. A few commenters point to the broader context of climate change and the urgency of addressing it, regardless of the specific findings of this study. One compelling comment argues that reducing emissions remains crucial, even if this particular feedback mechanism proves less significant than suggested. Another highlights the potential impact of reduced cloud cover on ecosystems, particularly deserts.
The Hacker News thread linked discusses the Science article "Earth's clouds are shrinking, boosting global warming." Several commenters express skepticism about the certainty of the findings, citing the complexity of cloud behavior and the difficulty of modeling it accurately.
One commenter points out that clouds are notoriously difficult to simulate in climate models, and that changes in cloud cover are a significant source of uncertainty in climate projections. They suggest that the observed shrinking cloud cover could be a temporary fluctuation rather than a long-term trend. This sentiment is echoed by others who emphasize the chaotic nature of weather systems and the need for longer-term data to confirm the study's conclusions.
Another commenter raises the issue of solar cycles and their potential influence on cloud formation, questioning whether the observed changes might be related to solar activity rather than solely to anthropogenic warming. This prompts a discussion about the relative contributions of various factors to climate change.
Several commenters discuss the limitations of observational data and the challenges of distinguishing between cause and effect in complex systems like the Earth's climate. They note the possibility of feedback loops, where changes in cloud cover could be both a cause and a consequence of warming.
Some commenters express concern about the potential implications of shrinking cloud cover, highlighting the role of clouds in reflecting sunlight and regulating the Earth's temperature. They worry that a decrease in cloud cover could exacerbate global warming and lead to more extreme weather events.
There is also discussion about the reliability of climate models and the importance of scientific skepticism. Some commenters caution against overinterpreting the study's findings, while others emphasize the need to take action to address climate change even in the face of uncertainty.
A few commenters provide links to related research and resources, offering additional context and perspectives on the issue of cloud cover and climate change. Some of these links lead to discussions about specific cloud types and their differing effects on the climate system.
Overall, the comments reflect a mix of skepticism, concern, and cautious optimism. While some question the certainty of the study's findings, many acknowledge the potential seriousness of shrinking cloud cover and the need for further research to understand its implications. The thread highlights the ongoing debate about the complexities of climate change and the challenges of predicting its future trajectory.