What’s the difference between climate and weather models? It all comes down to chaos

Nadia Piet/AIxDESIGN & Archival Images of AI / Better Images of AI , CC BY-SA Andy Hogg, Australian National University; Aidan Heerdegen, Australian National University, and Kelsey Druken, Australian National UniversityWeather forecasts help you decide whether to go for a picnic, hang out your washing or ride your bike to work. They also provide warnings for extreme events, and predictions to optimise our power grid. To achieve this, services such as the Australian Bureau of Meteorology use complex mathematical representations of Earth and its atmosphere – weather and climate models. The same software is also used by scientists to predict our future climate in the coming decades or even centuries. These predictions allow us to plan for, or avoid, the impacts of future climate change. Weather and climate models are highly complex. The Australian Community Climate and Earth System Simulator, for example, is comprised of millions of lines of computer code. Without climate and weather models we would be flying blind, both for short-term weather events and for our long-term future. But how do they work – and how are they different? The same physical principles Weather is the short-term behaviour of the atmosphere – the temperature on a given day, the wind, whether it’s raining and how much. Climate is about long-term...

Read More........→February 11, 2025

Nasa's Sampex Mission: A Space Weather Warrior

Image above: An artist's rendition of the Solar, Anomalous, and Magnetospheric Particle Explorer or SAMPEX. Credit: NASA. NASA's very first small explorer, the Solar, Anomalous, and Magnetospheric Particle Explorer or SAMPEX, was launched July 3, 1992 to study the zoo of particles and cosmic rays surrounding Earth. Surviving much longer than its expected mission of three years and providing invaluable observations for those who study space weather, the SAMPEX mission is now almost over. In early November, the spacecraft's orbit will decay enough that it will re-enter Earth's atmosphere, burning up completely on re-entry. When SAMPEX launched, the sun was just finishing the peak of its 11-year solar cycle and beginning to move toward solar minimum. Scientists were eager to watch what happened in near-Earth space in those first few years, as eruptions on the sun shot out energy and solar material and eventually tapered down into a period of quiet. However, those same effects were also predicted to lead to the spacecraft's demise. As the sun once again ramped up to solar maximum around 2000, the sun's output would create enough atmospheric drag that SAMPEX was expected to tumble out of its stable orbit. Contrary to such predictions, SAMPEX is still in orbit having survived that maximum and continuing in orbit long enough...

Read More........→November 14, 2012