March 2019: Earth’s Second Warmest March on Record

Our global temperature continued its upward trend last month with March 2019 marking the second warmest March ever recorded on this planet. Only March 2016 was warmer.

According to a report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for the month – over both land and sea surfaces – was 56.81°F. That is 1.91°F above the 20th-century average. March was also the 411th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

While heat dominated most of the planet in March, some places were particularly warm, including Alaska, northwestern Canada, as well as  large parts of Europe and Asia. These soaring temperatures are largely attributed to the long-term trend of human-caused climate change.

For many people in the contiguous US, especially in the northern and central parts of the country, this March was relatively cold. To put this disparity into context, consider that the United States constitutes less than 2% of the total surface of the Earth. This detail  also highlights the fact that climate change is a complex global phenomenon that involves much more than the short-term weather conditions that are happening in any one part of the world.

Year to date, the first three months of 2019 were the third warmest such period of any year on record. Global temperature records date back to 1880.

March 2019 was the planet’s second warmest March on record. Credit: NOAA

 

Do April Showers Really Bring May Flowers?

The phrase, “April showers bring May flowers “ has been around for centuries. It is derived from a poem written in the 1500s by Thomas Tusser – an English poet and farmer. This old adage, however, does not hold true in the northeastern United States.

Coming on the heels of the snowy months of winter, April typically produces more rain than snow. Many people, therefore, consider it a rainy month. Since water is necessary for the overall survival of plants, they also associate it with the bloom of flowers in May. Nevertheless, according to botanists, perennials – the plants that go dormant in winter and re-grow in the spring – are more dependent on the soil moisture derived from winter snowmelt and the long-term local precipitation pattern.

In the end, though, temperature is the most significant factor in determining when a flower will bloom. As soon as the weather becomes more spring-like, flowers will start to blossom, regardless of how much it rained in April or whatever the prior month was. That said, a “false spring” – a warm spell that triggers flowering but is followed by a hard frost – can kill the fragile blooms.

It is also worth noting that April is not typically the wettest month of the year for most places in the US. In New York City, July, on average, takes that honor because of the downpours associated with its strong summer thunderstorms.

Spring Peonies. Credit: Melissa Fleming

Weather Safety: Flooding and the Power of Water

It is no secret that heavy rain can cause flooding. However, it can be surprising to learn how little water is required to create significant impacts.

As anyone who carries a water bottle knows, water is heavy. In fact, just one cubic foot of fresh water weighs 62.4lbs (28.3kg).  Multiplied many times over, raging floodwater can carry away or destroy most things in its path. Moving at just 4-mph, water has enough force to cause structural damage to an average home.

Flowing floodwaters can also pose a danger when hiking or driving. According to NOAA, it only takes six inches of fast moving water to knock a person off their feet. Twelve inches of water can sweep a small car off the road and eighteen to twenty-four inches can float most large vans and SUVs.

Since it is impossible to know how deep water is just by looking at it, it is best to err on the side of caution. As the saying goes, “Turn around, don’t drown!”

Credit: NWS/NOAA

Climate Change is Making Allergy Season Longer

Spring is a season of rebirth. As temperatures warm, plants awaken from winter dormancy, generate pollen, and produce beautiful blooms. For allergy sufferers, however, the season can be a double-edged sword. With climate change extending the growing season, the outlook for people with seasonal allergies is less than rosy.

Across the US, the growing season – the period between the last and first freezes of the year – has lengthened by an average of two weeks since the 1970s, according to Climate Central. That means pollen allergies are staring earlier in the spring and lasting longer into the autumn. Tree pollen comes out in the spring, grass pollen strikes in the summer, and weed pollen is prevalent in the fall.

If global warming continues unchecked, studies show the growing season, and therefore the allergy season, expanding even further.

These changes to the growing season, like other climate change impacts, vary from region to region. The largest increase has been noted in the western states, according to the National Climate Assessment. Here in NYC, the growing season has increased an average of 21 days between 1970 and 2018.

Rising temperatures, however, are not the only factor for worsening allergy conditions. The carbon dioxide (CO2) in the air that causes the atmosphere to warm also plays a more direct role. When plants, particularly ragweed, are exposed to higher levels of CO2, they produce more pollen. Therefore, as concentrations of atmospheric CO2 continue to increase, pollen production will intensify.

March 2019 Came in Like a Lion and Went Out Like a Lamb in NYC

March 2019 felt like a weather roller coaster in New York City. Producing several days of weather whiplash, highs ranged from a frigid 26°F to an unseasonably balmy 75°F. In the end, however, these extremes nearly balanced each other out. The city’s mean temperature for the month was 41.7°F, which is only 0.8°F below average.

In terms of precipitation, rainfall was also slightly below normal. In total, Central Park reported 3.87 inches of rain, which is 0.49 inches below average for the month.

Snowfall, on the other hand, was abundant. After experiencing a snow drought for most of the winter, the first few days of March produced 10.4 inches of snow in Central Park.That is more snow than the city saw in November, December, January, and February combined. March, on average, typically only brings the city 3.9 inches of snow.

March 2019 felt like a temperature roller coaster in NYC. Credit: The Weather Gamut

Hurricane Names Florence and Michael Retired by WMO

There will never be another hurricane by the name of Florence or Michael. The World Meteorological Organization (WMO) has announced that it is officially retiring these names from its list of Atlantic cyclones.

The WMO is responsible for naming tropical storms and hurricanes around the world.  It maintains a set of six rotating lists for each hurricane-prone region. After a six-year cycle, names are re-used.  Names are only retired when a storm was particularly noteworthy – causing a large number of fatalities or an extraordinary amount of damage.

Hurricane Florence. Credit: NOAA

The 2018 Atlantic Hurricane Season was active, but two storms were particularly destructive. Hurricane Florence made landfall in North Carolina in September as a cat-1 storm and dumped a massive amount of rain on the area. Traveling inland, it caused catastrophic flooding in parts of both North and South Carolina. In Elizabethtown, NC, 35.93 inches of rain was reported, making it the wettest tropical cyclone on record for the state. For the contiguous US, it ranked as the eighth wettest.

Hurricane Michael. Credit: NOAA

In October, Hurricane Michael hit the Florida panhandle as a cat-4 storm. With winds measured up to 155mph, it was the strongest storm on record to strike the region and the third strongest storm to make landfall in the continental US. Its powerful winds and storm surge flooding decimated the Panama City area.

To date, according to the National Hurricane Center, 89 storm names have been retired since the current naming system began in 1953. The 2005 hurricane season holds the record for the most retired names – five – in one season.

Starting in 2024, when last year’s list is recycled, the names Florence and Michael will be replaced by Francine and Milton.

The 2019 Atlantic hurricane season officially begins on June 1.

Earth Posts 5th Warmest February and 4th Warmest Dec-Feb Season on Record

Our global temperature continued its upward trend last month. February 2019 marked not only the fifth warmest February, but also closed out the planet’s fourth warmest December – February season on record.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for February – over both land and sea surfaces – was 55.32°F, which is 1.42°F above the 20th-century average. This February also marked the 410th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

The three-month period of December, January, and February – meteorological winter in the northern hemisphere – was also unusually warm. NOAA reports that Earth’s average temperature for the season was 1.51°F above the 20th century average of 53.8°F. That makes it the fourth warmest such period on record.

While heat dominated most of the planet this season, some places were particularly warm, including Alaska, Europe, Australia, and parts of Russia and Asia. Here in the contiguous US, this winter ranked among the warmest third of the nation’s 125-year period of record.

Coming on the heels of 2018 – the Earth’s fourth warmest year on record – these soaring temperatures are largely attributed to the long-term trend of human-caused climate change. Global temperature records date back to 1880.

Credit: NOAA

A Look at the Science Behind the Spring Equinox

Today is the Vernal Equinox, the first day of spring in the northern hemisphere. The new season officially begins at 21:58 UTC, which is 5:58 PM Eastern Daylight Time.

Our 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 spring 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 winter solstice in December, the arc of the sun’s apparent daily passage across the sky has been getting higher and daylight hours have been increasing. Today, the sun appears directly overhead at the equator and we have approximately equal hours of day and night. The word “equinox” is derived from Latin and means “equal night”.

As a transitional season, spring is a time when the chill of winter fades away and the warmth of summer gradually returns. The most noticeable increases in average daily temperature, however, usually lag the equinox by a few weeks.

Earth’s solstices and equinoxes. Image Credit: NASA

A Look at Rainbows and their Legendary Pots of Gold on this St Patrick’s Day

According to Irish folklore, a pot of gold can be found at the end of a rainbow. In reality, however, it is impossible to locate the terminus of this optical phenomenon.

Refraction and reflection inside a raindrop. Credit: Met Office

For a rainbow to form, rain has to be falling in one part of the sky while the sun is out in another. The water droplets in the air act like prisms that refract and reflect the sunlight, revealing the colors of the visible spectrum. Red is refracted the least and is always on the top of a single bow while blue is on the bottom. Since we only see one color from each drop, it takes a countless number to produce a rainbow.

A double rainbow is seen when the light reflects twice inside the raindrops. Since each reflection weakens the intensity of the light, the second bow appears dimmer. The order of the colors is also reversed, with blue on top and red on the bottom.

That said, these colorful arcs are not physical entities that can be approached. No matter how close they appear to be, they are always tantalizingly out of reach. Nevertheless, most people consider seeing one to be a treasure with no gold required.

With a little luck, you can spot a rainbow if you face a moisture source – rain or mist from a waterfall – while the sun is at your back.

Happy Saint Patrick’s Day!

Rainbow and faint second rainbow form after a rainstorm in Bermuda. Credit: Melissa Fleming

A Spring Preview Melts March Snow in NYC

The calendar says March, but it felt more like May in New York City on Friday.

The temperature soared to 75°F in Central Park, missing the record high by just 2°F. But, with the mercury only dropping to 49°F at night, it did tie the record warm low temperature for the date that was set in 1913.

The normal high and low temperatures for this time of year in NYC are 49°F and 35°F, respectively.

With below normal temperatures dominating the beginning of March, this sudden warm up felt like weather whiplash. Just a week earlier, there was snow on the ground with snowmen dotting the landscape in parks across the city.

But, as with most things that go up, they must also come back down. Cooler conditions are expected to return over the weekend.

What a difference a week can bring: the same snowman in Central Park one week apart. Credit: Melissa Fleming