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Christina Loren is a Certified Meteorologist with an enthusiastic passion for atmospheric science.

Tarantula Mating Season Means Fall Is On It's Way

By: Christina Loren

     It is late August and tarantula mating season has started in the Bay Area. Male California Tarantulas are looking for love and instead of waiting for the cloak of nightfall, these nocturnal critters are coming out earlier, in the twilight of dusk. I saw this one on a a hiking trail in the South Bay hills. Tarantula mating season typically takes place late summer into early fall and after 5-8 years of maturing in solitude, males are on the prowl to reproduce with female mates. These large hairy spiders should be approached with caution although they are not looking to harm humans. They have one thing on their mind and that is reproduction. When I encountered this one it stopped in the middle of the trail and remained completely still until I moved along. Male tarantulas are searching for the females silk-lined burrows. Hopefully this guy was able to find one later in the night. What is interesting is that after male tarantulas find a mate they only live for an additional 3-6 months whereas females can live for another 25 years. Tarantulas are most commonly seen by humans in the high elevation trails, roads, and even gardens of the Bay Area.

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posted by Christina Loren @ 12:33 PM, ,

A Simple Explanation of How Hurricanes are Named

By: Christina Loren

Tropical storms and hurricanes are capable of devastating large populations and destroying wide swaths of property. Although the National Hurricane Center does the heavy lifting of forecasting and tracking tropical cyclones in the United States, they are not responsible for the names that these powerful storms receive. Instead, the World Meteorological Organization is in charge of naming tropical storms and hurricanes. Tropical depressions do not get names unless they strengthen and develop and meet certain criteria. Simply stated, a storm must have max wind speeds of 39 mph or more around a closed center of circulation in order to reach tropical storm strength and receive a name. If max winds reach 74 mph or more around a closed low, the storm is then upgraded to a hurricane.

During hurricane season it is not uncommon for multiple tropical cyclones to occur at the same time. Assigning names to these powerful systems helps to eliminate confusion and eases keeping tabs on the track and intensity of each storm. That is why the WMO creates a list of names in alphabetical order that can be repeated after a six year interval. However, when a storm is exceptionally destructive, such as Hurricane Katrina or Hurricane Andrew, the name is retired.

Hurricane Irene
August 20, 2011 - August 28, 2011

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posted by Christina Loren @ 1:28 PM, ,

What is El Niño?

By: Christina Loren

        An interesting meteorological phenomenon that dictates weather conditions for a given area is the influence of coastal winds on ocean currents. In the open ocean surface currents are directly impacted by global wind patterns. Simply stated, El Niño describes a change in trade wind patterns leading to unusually warm ocean currents in the Pacific Ocean. This alteration in surface ocean temperature has a tendency to create extreme weather changes, specifically between October through March, with peak conditions from December through February. Some of the impacts typically associated with El Niño are a lack of precipitation for parts of Indonesia and Australia and the development of strong storms packed with ample moisture that tend to aim at California and areas in the southwestern United States. Although these effects are characteristic of a strong El Niño pattern, there is no guarantee that this year's event will produce the flooding rain we saw in 1997-1998 in California. In the same way that no two storms are the same, no two El Niños are the same either. There are other atmospheric variables at play that will likely influence how this year's rain season will pan out. Nonetheless, I would be willing to bet that El Niño will at the very least provide the state of California with average rainfall for the 2015-2016 rainy season.

Read Christina Loren's answer to What are the explanations of El Nino? on Quora

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posted by Christina Loren @ 12:27 PM, ,

Wild Weather at 10,023 feet on the Haleakala Shield Volcano

By: Christina Loren

The summit of Haleakala is 10,023 feet above sea level and a stunning location to watch the sunrise. Haleakala is a shield volcano and formed over 75 percent of the island of Maui. The weather at the summit of Haleakala changes rapidly and on any given day the weather can vary dramatically from sunny and hot to rainy and cool in a matter of minutes. There is typically a 30º difference between temperatures at the summit of Haleakala vs. the temperature on the coast. Rain is common on the volcano so if you plan on visiting it is a good idea to prepare for a variety of differing weather conditions and rain gear as well as sun glasses will likely serve you well on the same trip. 

Christina Loren on Vine:

 Sunrise from the summit of Halakeala at 10, 023 feet at 5:50 a.m.

The Shadow of the mountain paints a purple haze at sunrise on top of Haleakala.

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posted by Christina Loren @ 12:50 PM, ,

Sea Turtles Typically Live and Thrive in Warm Tropical Waters

By: Christina Loren

Sea turtles love the warm tropical waters that surround the Hawaiian island chain. What is interesting about sea turtles is that they  need to breathe oxygen for survival and surface for air. They can actually hold their breath for several hours at a time. A sleeping sea turtle can stay underwater for 5-7 hours.

Video of a Sea Turtle Coming Up For Air In Napili that was shot from my IPhone

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posted by Christina Loren @ 9:11 PM, ,

What is the Difference Between Weather and Climate

By: Christina Loren

        The distinction that separates climate and weather is time. Climate is an average measure of weather for a specific location over a long period of time, typically 30 years or more. Weather describes the short-term changes in atmospheric conditions like temperature, humidity, wind, and rainfall for a defined area. There are certain parameters that must be met over a long duration of time in order to classify an area as a desert. For example, desert climates typically receive less than 10 inches of rain per year. 

     Here in California we are dealing with mandatory water restrictions due to four consecutive years of below average rainfall. What is interesting is that drought conditions may improve dramatically next year as we are noticing good signs for a strong El Nino in the Pacific Ocean. This is significant because with a strong El Nino there is a high likelihood of heavier than average rainfall for the upcoming rainy season in California.

Read Christina Loren's answer to At what point do we stop saying "area X is suffering a years long drought" and just say "the climate has changed, area X is now classified as desert"? on Quora

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posted by Christina Loren @ 4:46 PM, ,

How do Meteorologists Forecast the Weather?

By: Christina Loren

        The forecast is a function of a multitude variables that all need to be taken into account in order to assess what future weather conditions will occur. Current and expected temperature, dew point, humidity, barometric pressure, approaching storms, etc. all need to be investigated in order to predict what will happen next. There are a number of different methods that can be used to generate an accurate weather forecast, however this is entirely dependent on the experience level of the forecaster and the amount of data that is available to him/her. I have found that the persistence method of forecasting is most valuable in California, pending that there are no approaching storm systems or substantial changes in moisture content on the horizon. The persistence method is based on common sense. If there are no drastic changes in temperature, dew point, humidity, barometric pressure, etc. in the forecast from one day to the next, the weather conditions will likely end up being very similar both days. This approach works great in California in the Spring and Summer.

Read Christina Loren's answer to How is the weather forecasted? on Quora

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posted by Christina Loren @ 7:57 AM, ,

The Science Behind the Classification of Rain vs. Drizzle

By: Christina Loren

Meteorological Terminology 101 from Meteorologist Christina Loren: The difference between rain and drizzle is actually dependent on the size of the water droplet falling from the sky. The truth is, this is common sense and most people know what the difference is in rain and drizzle. What you may not know however, is that there are concise parameters that differentiate between the two scientifically.

Read Christina Loren's answer to Why are raindrops too small in size? Do they have the same size when they fall from the clouds? on Quora

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posted by Christina Loren @ 11:06 PM, ,