Today is Arbor Day, a holiday that honors trees. While their beauty has been celebrated in countless poems and images over the years, trees are much more than aesthetic figures in the landscape. They are an essential part of the global ecosystem and play an important role in fighting climate change.
Trees also provide shade. In cities, this helps reduce the urban heat island effect. More specifically, according to studies by the US Forest Service Center for Urban Research, neighborhoods with well-shaded streets can be 6-10°F cooler than communities without trees. This natural cooling benefit, in turn, lessens the need to run energy-consuming air conditioners during the warm summer months.
With rising temperatures leading to more heavy rain events, trees also help mitigate the impacts of flooding and landslides. Their root systems catch rainwater and reduce soil erosion. Climate Central, a non-profit environmental news organization, says trees help prevent nearly 400 billion gallons of runoff every year in the contiguous US.
So, as the saying goes “The best time to plant a tree is 20 years ago. The second best time is now.”
Every day is Earth Day, as the saying goes. But, today marks the official celebration.
The first Earth Day – spearheaded by Senator Gaylord Nelson of Wisconsin – was held on April 22, 1970. An estimated 20 million people attended rallies across the US to protest against rampant industrial pollution and the deterioration of the nation’s natural environment. Raising public awareness and shifting the political tide, these events helped put environmental issues on the national agenda. They helped lead the government to create the EPA and the pass of the Clean Air Act, Clean Water Act, and the Endangered Species Act.
Today, forty-nine years after the original, Earth Day is celebrated in nearly 200 countries around the world. Some communities have even expanded the celebration into a series of events for Earth Week or Earth Month. These continuing efforts to raise environmental awareness are more important than ever as we face the global challenges of climate change.
It felt more like June than April in New York City on Friday. The temperature in Central Park soared to 80°F, marking the city’s first 80-degree day of the year.
Topping out at 17°F above average, the day was unseasonably warm. However, it was not a record breaker. That honor belongs to April 19, 1976, when the mercury soared to 92°F. The low temperature was 58°F, which is also warmer than normal for the date.
This spring heat was the result of a ridge in the jet-stream that allowed warm southern air to move further north than it normally would at this time of year. These balmy conditions did not last long, though. A heavy rainstorm moved through the region over night and brought temperatures back to more seasonable levels.
According to a report by the National Hurricane Center, the storm’s winds reached 160mph when it made landfall near Mexico Beach, FL. That is a 5mph increase from the estimate used last autumn. The agency says the uptick was the result of a re-analysis of reams of data, including aircraft winds, surface winds, surface pressures, satellite intensity estimates, and Doppler radar velocities. The review also took into account data that was not available in real time.
In the grand scheme of things, an increase of 5mph may not sounds like a lot, but it puts Michael in rare company. It now ranks as the fourth category-5 storm on record to make landfall in the US. The other three were the Labor Day Hurricane of 1935, Hurricane Camille in 1969, and Hurricane Andrew in 1992. Michael is also the third cat-5 storm to hit the Sunshine state.
Regardless of the technical upgrade and historic statistics, Hurricane Michael was a devastating storm that will be long remembered by those it affected. The storm claimed the lives of 16 people and caused an estimated $25 billion in damage. More than six months after coming ashore, much of the area is still recovering.
Hurricane Michael making landfall as a Category 5 storm along the Florida Panhandle on October 10, 2018. Credit: NOAA
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
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.
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!”
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.
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