Cassini, The Great Explorer

By: Jenna Hans

More than 20 years ago, NASA launched Cassini, a spacecraft that would give insight into an entire new world. Cassini spent almost 20 years in space exploring Saturn, its rings, moons, and magnetosphere. According to NASA JPL, Cassini observed Saturn’s unique hexagonal jet stream. The jet stream is a bit of a mystery since scientist don’t know exactly why it flows the way it does. Cassini also recorded lightning on Saturn, hurricane like storms, and since Saturn’s “30 year storm” came 10 years early, scientists were able to get an amazing look at the storm.

Throughout its mission, Cassini also discovered interesting things about Enceladus and Titan, two of Saturn’s moons. The spacecraft was able to discover geysers on Enceladus, the icy ocean moon. After this mission, Enceladus has become a point of interest planet where scientist think life might exist. On Titan, Saturn’s largest moon, Cassini found methane pools and evidence that there might actually be an underground ocean on the moon.

During its almost 20 years of space exploration Cassini discovered and photographed things that people could have never even dream of. It opened our eyes to brand new and exciting information and leaves us all wondering what else is out there waiting to be discovered. In its last moments, after almost 20 years of exploring the depths of space, Cassini began its descent toward Saturn where it burnt up and was destroyed. Committed to science and exploration, Cassini sent in information and data up until its final moments, making the ultimate sacrifice for science. The amazing feats of Cassini remind us of the doors that technology can open for us, and just how amazing life beyond our planet really can be.

See Cassini’s total timeline here: https://saturn.jpl.nasa.gov/the-journey/timeline/#the-grand-finale

Read more about Cassini’s discoveries here: https://saturn.jpl.nasa.gov/

See the full gallery of Cassini’s images: https://saturn.jpl.nasa.gov/galleries/images/?page=0&per_page=25&order=created_at+desc&search=&condition_1=1%3Ais_in_resource_list&category=51&fancybox=true&href_query_params=category%3Dimages

Nuclear Radiation and Aviation

By: Warren Qualley

Like a lot of aspects that circle our daily lives and the environment, nuclear radiation and aviation is an area which by its nature, of being transported in the atmosphere, has become a part of meteorology.

The accidental (or intentional) release of nuclear radiation into the atmosphere is a very emotional issue. The first occurrence was the accident at the Chernobyl nuclear facility in the Ukraine in 1986. (1)  From an airline perspective, the main concern was the safety of passengers and the potential, but unknown impact on aircraft. The fact that humans can’t smell or see radiation yet know that it can be deadly makes it very frightening.

In the wake of the accident at Chernobyl, scientists had to get weather data for that region, and then plug that into computer dispersion models to get a 4-dimensional view of its radiations likely trajectory. Airlines needed to know the areas on the ground and in the sky to avoid an encounter with the radiation “cloud”.

More recently, the nuclear accident at Fukushima in Japan was another example of an ominous cloud of radiation that presented risks to aviation. One of the biggest challenges in this and other similar events was getting ongoing accurate and timely information, which the computer dispersion models required. The governmental authorities are responsible for the flow of the information, yet they are concurrently busy with assisting the victims and containing the hazard. Commercial airlines were in constant contact with the authorities in these events and always acted conservatively to ensure the safety of their passengers and employees.

More will be learned from these events, with the goal of protecting people. There are currently developed technologies such as the MeteoSwiss which operates the CN-MET wind analysis and forecasting system for nuclear incidents in Switzerland and neighboring countries. (2) The accurate measurements and high-resolution model forecasts allows for determinations of wind fields and weather developments around Switzerland’s nuclear power stations and those in neighboring countries and thus to calculate the dispersion of contaminated air masses. This type of technology allows for the safety of those that would be in the path of harmful radiation clouds after a nuclear accident.

Citations:

(1). http://www.world-nuclear.org/information-library/safety-and-security/safety-of-plants/chernobyl-accident.aspx

(2). http://www.meteoswiss.admin.ch/home/measurement-and-forecasting-systems/warning-and-forecasting-systems/meteorology-for-nuclear-accidents.html

Weather, Climate, and Volcanoes

By: Marina Kobasiuk

With the volcanic eruption in Guatemala headlining on the news now, along with the continued fissures in Hawaii, there is considerable talk on the effects of volcanoes on weather and climate. The immediate concerns with local weather is usually related to rain and clouds as precipitation becomes harder to predict with ash helping clouds form. Acid rain can also begin to occur, along with other shorter term conditions that result from large amounts of debris in the air, according to the United States Geological Survey. As sulfuric acid released into the air dissolves into water it creates an acidic precipitation that can impact soil and waterway acidity, or cause gradual erosion of other structures. Dust and ash can also cause volcanic smog which is a major health concern for people near any eruption or downwind of one. This is one of the major concerns in Hawaii due to so much magma interacting with ocean water and producing toxic haze.

Meanwhile in Guatemala it has been pyroclastic flows, a massive cloud of ash, lava, and toxic gases all at intensely high temperatures, that have caused the majority of damage so far. But with these effects also come sediment depositions that enrich soil with nutrients for crops that make farming more viable in certain areas. And even aesthetically, some of the most interesting sunrises and sunsets on record occur in the days and weeks after an eruption as ash interacts with clouds and sunlight.

In the long term, volcanoes are thought to be influencers in shifts in climate. In any kind of eruption lots of gases and physical particles are expelled into the air. While some break down or fall back to the surface eventually, with more violent eruptions some of these particles can reach high levels of the atmosphere and remain for years. Physically dust and ash can prevent sunlight from reaching the planet and cause a cooler environment, but on the opposing side greenhouse gases such as carbon dioxide released by volcanoes can also absorb and emit heat back down to the planet, creating a warming trend. This makes the exact influence of a volcano hard to pin down.

These long term effects are more gradual since a volcano releases a relatively small amount of all of these pollutants due to it being a single isolated event, and the planet is often able to adjust with only moderate shifts. On record there are connections between large scale eruptions and major climate shifts, such as Mount Pinatubo in 1991 and the almost half a degree Celsius drop some regions saw after. So observing these two events happening close together will be difficult, but the effects on the regions local weather and the climate shifts for the coming seasons will be important to watch to see how these changes influence the planet.

Summary: There are two major volcanic events happening currently, so here’s a brief look at weather, climate, and how they relate to eruptions.