Daily Archives: September 23, 2015

Celebrating Fourth Blogiversary

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Four years ago today, I started writing this blog and it has been both an amazing and rewarding journey.

Initially begun as a way to deepen and share my knowledge about weather and climate change, this blog has allowed me to expand on my interests and concerns in ways that I never thought possible four years ago. This past year, I developed a selection of slide presentations about climate change and have spoken at a variety of venues, including a national conference. It has also introduced me to many wonderful people working in this fascinating field. Looking ahead, I am hoping to add some video content to the blog over the next few months. So, stay tuned!

As always, thank you for reading!

4_Blogiversary

Image Credit: Maria Elena

Autumnal Equinox 2015

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Today is the Autumnal Equinox, the first day of fall in the northern hemisphere. The new season officially began at 8:21 UTC, which is 4:21 AM Eastern Daylight Time.

The astronomical seasons are a product of the tilt of the Earth’s axis – a 23.5° angle – and the movement of the planet around the sun. During the autumn months, the Earth’s axis is tilted neither toward nor away from the sun. This position distributes the sun’s energy equally between the northern and southern hemispheres.

Since the summer solstice in June, the arc of the sun’s apparent daily passage across our sky has been moving southward and daylight hours have been decreasing. Today, it crossed the equator and we have approximately equal hours of day and night. The word “equinox” is derived from Latin and means “equal night”.

With the sun sitting lower in the sky and daylight hours continuing to shorten, Autumn is a season of falling temperatures.  According to NOAA, the average high temperature in most US cities drops about 10°F between September and October.

Solstices and Equinoxes. Credit: NASA

Earth’s solstices and equinoxes. Image Credit: NASA

Equinox

The Earth’s axis is tilted neither toward nor away from the sun on the Equinox. Image Credit: NASA