 DISCUSSION: Last month, the climate of the Triassic period was explored. If you missed it, be sure to check it out here! This is now the second of three pieces to look at the climate of the Mesozoic era, where this month’s focus will be on the Jurassic period. The Jurassic period occurred between 199 and 145 million years ago. Dinosaurs had begun to evolve and thrive during the Triassic period, but the large increase in dinosaur diversity, as well as the presence of new plesiosaurs (marine reptiles) and pterosaurs (flying reptiles), began to manifest itself during the Jurassic period. In the early Jurassic, animals were still similar throughout the world due to the connected nature of the continents – however, these continents slowly started to drift apart, allowing for a greater diversity of dinosaurs in the mid to late Jurassic. As continents drifted apart, more land masses and coastlines were created, allowing oceans to widen and sea levels to increase. Epicontinental seas (also known as inland seas) started to form due to these rising sea levels. These rising sea levels caused an increase in the humidity level, which marks a big difference between the Triassic and the Jurassic. While the Triassic climate was dry, the Jurassic climate was wetter and more humid, and almost resembled a rainforest in the tropical areas.  These rainforest-like conditions paved the way for lush vegetation to grow, slightly increasing the carbon dioxide levels, therefore creating a “greenhouse” climate and warming throughout the world. Vegetation in the Jurassic period included a more diverse set of plants, catering to all of the different types of specialized dinosaurs that had started to evolve during this time. Some examples of these specialized dinosaurs include tetanurans (both large and small carnivores), thyreophorans (armored herbivores, such as stegosaurus and ankylosaurs), and sauropods (large herbivores, such as Brachiosaurus and Diplodocus). The many different types of plants that appeared in the Jurassic provided resources for all the different types of herbivores. The long-necked sauropods could spend their time devouring tall conifers, and the ground-level head of the stegosaurs and ankylosaurs could graze on the low-lying plants, such as ferns and horsetails. One of the most diverse dinosaur fossil deposition on earth, the Morrison Formation, was created during this time. The Rocky Mountains began to uplift during the Jurassic period, and as they weathered, sands became deposited at the sides of the mountain into lakes, swamps, and streams. In the early twentieth century, this was the place to be to find fossils!  Stay tuned for next month, where the Cretaceous period is covered in the last of three pieces on the climate of the dinosaurs. If you want to read more storeis like this, and learn more about the geosciences, be sure to visit here!
References: https://sciencing.com/climate-jurassic-era-4932.html https://www.nps.gov/dino/learn/nature/morrison-formation.htm http://www.dailymail.co.uk © 2018 Weather Forecaster Joseph Fogarty
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 DISCUSSION: Studying dinosaurs was a highlight for many young elementary school students in science class. Triceratops, Stegosaurus, and the notorious Tyrannosaurus Rex are all fascinating creatures that nearly everyone remembers. However, the climate of the different periods of the Mesozoic era (Triassic, Jurassic, and Cretaceous) is not something everyone remembers. Yet it is important to study, as the climate of any particular period determined which types of animals thrived while others struggled for survival. This is the first of three pieces that intend to look at the climate and its relation to dinosaurs in the three periods of the Mesozoic Era. The Triassic period, which occurred between 251 million and 199 million years ago, marked the first appearance of the dinosaurs. The Permian-Triassic extinction event, which happened 251 million years ago, is the largest known extinction event; a total of about 95% of all life went extinct. This event marked the boundary of the Permian and Triassic period, also known as the P-T boundary. Since almost all species became extinct, there was a very low biodiversity at the start of the Triassic. A possible cause of the P-T extinction is the massive eruptive event of the Siberian lava traps, a large region of volcanic rock in Siberia, Russia. As these volcanoes erupted, the Earth underwent a global warming due to the massive CO2 emission. This warming created an uninhabitable atmosphere, which made the land mostly barren for the 5% of organisms that survived the extinction event. Another consequence of these eruptive events was oceans becoming an anoxic environment, i.e. they had little to no dissolved oxygen. This made marine life inhabitable as well at the end of the Permian period. The geography of the Triassic period was a major factor in shaping the climate. The supercontinent Pangea started to take shape, with all continents together as one. The fact that all land was attached, combined with the low biodiversity of animals post-extinction, meant life was similar everywhere on Earth. The climate of Pangea was very hot and dry, especially in the interior. This may explain why reptiles and dinosaurs became dominant, and not mammals. Near coastal regions, a seasonal monsoon climate prevailed as well. The land was barren of plant life, but certain plants did survive the P-T extinction. These plants included ferns, woody plants, and gymnosperms (a plant with cones or pollen spores).  The surviving groups of animals that survived the P-T extinction were therapsids, who were mammal-like reptiles, and archosaurs, a more reptile-like organism. The archosaurs had evolved into dinosaurs by the mid-Triassic, and therapsids had almost gone extinct, meaning that the hot and dry climate was better suited to these reptilian-like animals. Many of these reptiles evolved into sprawlers, and some evolved into bipedal creatures (creatures who walked on two legs), such as Coelophysis (below). Towards the end of the Triassic, another group had evolved from the surviving archosaurs, called the pterosaurs (a term for winged reptiles).  Stay tuned for next month, where the climate and dinosaurs of the Jurassic period is covered. If you want to learn more about the geosciences, be sure to visit here!
References: https://www.livescience.com/43295-triassic-period.html https://upload.wikimedia.org/wikipedia/commons/8/80/Coelophysis_size.jpg http://www.scotese.com/newpage8.htm © 2018 Weather Forecaster Joseph Fogarty  DISCUSSION: Have you ever taken a vacation to a city and then drove by a rural area for a pit stop? Have you stopped and thought, “man it sure is cooler here than in the city?”
There’s a name for this feeling. It’s called the Urban Heat Island. In simpler terms, it says that cities are 1-5°C warmer than rural areas. The effects of this phenomenon can go beyond city limits. These are the reasons for the Urban Heat Island: reduction in evapotranspiration, composition of materials in the city, pollution, and excess heat from human (anthropogenic) activity. By definition, evapotranspiration is when water gets transferred to the atmosphere by evaporation from the land and transpiration from plants. Unless there is a garden or park within city limits, there is reduced vegetation in the city. Therefore, this allows for more sensible heat and warmer temperatures. In addition to this, areas where water can’t be absorbed within the city promote runoff. Urban areas have lower albedos, which means less reflection and more absorption of sunlight. The construction materials have high heat capacities and thermal conductivity. These are defined, respectfully as, the ability to raise a degree of an object by 1 degree Celsius, and the ability to conduct heat. Energy is stored in the day and released at night. Pollution can act like a shield over the city. What is meant by this “shield of pollution” is that this “shield” can act as a barrier against outgoing longwave radiation from leaving. Once this radiation attempts to leave, the “shield” will just send it right back to the city. This explains the increase in nocturnal temperature in cities. The following things humans do can release heat: transportation, cooling apparatuses such as air conditioners, street lights, etc. In conclusion, the effects of urbanization can have an immediate effect on the weather. To learn more about Urban Weather, click here! “©2017 Weather Forecaster Jennifer Naillon  DISCUSSION: For the island of Bali in Indonesia, a maximum level 4 alert has been issued on the volcanic alert system. Mount Agung (pictured) had been spewing ash for about a week with increasing intensity, but heightened seismic activity has Indonesia’s disaster mitigation agency raising the urgency to those who live in the designated exclusion zone to evacuate as soon as possible. This danger area, about an 8 to 10 kilometer radius around the volcano, is in a prime spot for a major eruption. So far only 40,000 people have fled, but 60,000 are still waiting to leave. According to the governor of Bali, an additional 150,000 people may be called on to evacuate.
Currently 445 flights to and from Indonesia’s top tourist destination have been canceled, stranding about 59,000 unfortunate travelers. More information can be found here. To learn more about the Global Weather and Climate Center, be sure to click here! ©2017 Meteorologist Nicholas Quaglieri  DISCUSSION: Vanuatu, a nation of islands located in the Pacific Ring of Fire (between Australia and Hawaii), is home to about 280,000 people and stretches nearly 800 miles. Ranked as the country most at risk for natural disasters in the world, recent volcanic activity has now added to Vanuatu’s reputation. On the island of Ambae, recent activity from the Monaro volcano has forced the entire population of the island of approximately 11,000 to evacuate. Most of those who evacuated are being transported by boat or are airlifted to one of the other nearly 80 islands in the island chain.
With rocks and gas spewing from the volcano, the government has issued the second-highest alert possible in their volcanic alert system for the first time ever at Level 4 (Level 5 indicates an eruption is imminent). Although they can measure seismic activity, it is impossible to predict exactly when an eruption will occur. In addition, evacuations have been underway on the island of Bali in Indonesia. Mount Agung (in photo), a volcano located in the northeast region of the island, has been at its highest alert level for about a week. Nearly 134,000 people have been strongly urged to leave their homes. When the volcano last erupted in 1963, lava traveled 4.7 miles, ash was hurled up 12 miles, and about 1,100 people lost their lives. To learn more about the Global Weather and Climate Center, be sure to click here! ©2017 Meteorologist Nicholas Quaglieri  DISCUSSION: Within the past week, there have been definitive signs of activity in association with Mount Etna. As seen in the video above (courtesy of the Protezione Civile), there was a fairly large ash cloud emanating from close to the peak of Mount Etna (which is an active stratovolcano located on the east coast of Sicily, Italy, in the Metropolitan City of Catania, between the cities of Messina and Catania). As this eruption period continued through the course of the day back on February 28th, there were also other growing concerns. As a volcanic eruption occurs, there are often major concerns for a growing threat to commercial and private aviation interests.
This is due to the fact that as a volcanic eruption persists, increasingly larger amounts of volcanic ash are suspended into the localized atmosphere before spreading out from the point of origin (i.e., Mount Etna in this particular case) and affecting other geographic regions in and around the point source of the volcanic ash. This spreading out of the original volcanic ash plume occurs as the prevailing winds through the depth of the atmosphere transport the ash cloud in a given direction before being spread out in a more dispersed manner as the concentration of the ash cloud slowly decreases. Therefore, even after several days from the original eruption, any residual ash suspended in the atmosphere has the ability to damage aircraft engines along with ash ejected from any residual volcanic activity associated with Mount Etna. To learn more about other topics in applied meteorology, be sure to click here! ©2017 Meteorologist Jordan Rabinowitz |
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