October 2018: Earth’s Second Warmest October on Record

Our global temperature continued its upward trend last month with October 2018 marking the second warmest October ever recorded on this planet. Only October 2015 was warmer.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for the month – over both land and sea surfaces – was 58.65°F, which is 1.55°F above the 20th-century average. October also marked the 406th 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 this October, some places were particularly warm. These included eastern Russia, northern Australia, Alaska, and most of the east coast of the United States. These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in October, which means there was neither a warm El Niño nor a cool La Niña in the Pacific to influence global weather patterns.

For many people in the central US, however, October was relatively cool. These chilly temperatures, driven by a deep dip in the jet stream, helped cool the national average to 0.3°F below normal for the month. To put this disparity into context, consider that the contiguous United States constitutes less than 2% of the total surface of the Earth. This detail highlights the fact that climate change is a complex global phenomenon that involves much more than the short-term weather that is happening in our own backyards.

Year to date, the first ten months of 2018 were the fourth warmest such period of any year on record. Global temperature records date back to 1880.

October 2018 was the second warmest October ever recorded on this planet. Credit: NOAA

First Snow of the Season in NYC Broke Several Records

New York City saw its first snow of the season on Thursday and it was one for the record books.

According to the NWS, 6.4 inches of snow was measured in Central Park, setting a new daily record for the date. The previous record of 1 inch had been in place since 1906. It was also the earliest 6-inch one-day snowfall on record for the city and the largest one-day November snowfall since 1882.

These superlatives came as a bit of a surprise. The forecast originally called for a wintry mix with only a dusting of snow at the onset. However, the temperature was colder than expected and the snow hung on longer. This was largely the result of an area of high pressure to the north being stronger than forecast and therefore able to funnel air toward the city that was colder than anticipated. Closer to home, evaporative cooling also played a part.  The air near the surface was very dry as the storm moved into the area. This allowed some of the snow to evaporate as it fell, cooling the air even further. As result, the change over to rain was delayed by several hours.

While pretty to see, the snow caused a number of problems around the city. Widespread travel delays and falling trees were reported across the five boroughs. As it is only mid-November, many of the trees still had their leaves. The combination of the heavy, wet, snow piling up on the foliage, weighing down the branches, and high winds was too much to bear for many trees, even the healthily ones. Many fell across streets and sidewalks as well as on top of parked cars. The city’s Parks Department has reported receiving over 2000 service requests for downed trees and dangling limbs.

This storm clearly outperformed expectations and caught the city off-guard. On average, New York City sees 0.3 inches of snow for the entire month of November.

Record breaking November snowfall topples trees in NYC. Credit: Melissa Fleming

Deadly Wildfires Blaze in Northern and Southern California

California, once again, is ablaze with wildfires.

As of Tuesday, three major wildfires – defined as 100 acres or more – are burning in the Golden State.  Collectively, according to National Interagency Fire Center (NIFC), they have burned more than 200,000 acres and claimed the lives of 44 people. In terms of property damage, close to 8,000 homes and business have been destroyed and at least another 50,000 are at risk.

Sweeping through the wooded northern California town of Paradise, the death toll from the Camp Fire currently stands at 42. That makes it the deadliest wildfire in the state’s history. It surpasses the Griffith Park Fire, which killed 29 people in 1933. Sadly, with 200 people listed as missing, the death toll from this fire is expected to climb even higher in the coming days. It is currently only 30% contained.

At the southern end of the state, the Woolsey and Hill Fires have forced massive evacuations. Raging west of Los Angeles near Malibu and only 30% contained, the Woolsey Fire has charred more than 93,000 acres and destroyed more than 400 structures. The Hill Fire, currently at 85% containment, has scorched upwards of 4,500 acres.

Air quality issues are another concern with these wildfires. Well outside of the burn areas, many people are wearing masks to protect themselves from the smoke and ash carried in the wind.

These huge fires are largely the result of climate whiplash. California has distinct wet and dry seasons, but they have been extreme recently. After years of drought, the state saw increased precipitation over the past two winters that spurred explosive plant growth. Then during this past summer, which was unusually dry, all that vegetation turned to tinder.

Making matters worse, the region’s seasonal winds, known as the Diablo Winds in the north and the Santa Ana Winds in the south, kicked into high gear. Flowing from east to west, downslope from the mountains toward the coast, these winds warm from compression and dry out vegetation even further. They also fan the flames of any fire already burning and can cause it to spread very quickly.

To date, according to NIFC, 1.5 million acres in California have been burned by wildfires in 2018. That number, however, is expected to go up as these fires continue to spread.

The Camp Fire in Northern California seen from space. Credit: NASA

Film Looks at Climate Change as a National Security Issue

Today is Veterans Day, a day to honor the men and women who have served in the armed forces. As such, it seems an appropriate time to highlight “The Age of Consequences” – a film that looks at climate change through the lens of national security and global stability.

Directed by Jared Scott, the film features a number of interviews with members of the military. While quick to point out that climate change is not the sole cause of any particular conflict, they discuss how it acts as a “threat multiplier” or “accelerant of instability”.

More specifically, the film shows how water and food shortages, drought, extreme weather, and sea-level rise have stressed social tensions to the point of armed conflict and/or mass migration in some of the more volatile regions of the world. Released in 2016, the war in Syria, the rise of ISIS, and the European refugee crisis are prominently featured.

Watch the trailer here:

How the Santa Ana Winds Help Wildfires Spread

The Santa Ana winds are notorious for exacerbating wildfires in southern California.

These strong winds blow warm, dry air across the region at different times of the year, but mainly occur in the late autumn. They form when a large pressure difference builds up between the Great Basin – a desert that covers most of Nevada and parts of Utah – and the coastal region around Los Angeles. This pressure gradient funnels air downhill and through the passes of the San Gabriel and San Bernardino mountains toward the Pacific. Squeezing through these narrow canyons, the wind is forced to speed up. The Santa Anas, according to the NWS, can easily exceed 40 mph.

Originating in the high desert, the air starts off cool and dry. But as it travels downslope, the air compresses and warms. In fact, it warms about 5°F for every 1000 feet it descends. This dries out the region’s vegetation, leaving it susceptible to any type of spark. The fast-moving winds then fan the flames of any wildfires that ignite.

The Santa Ana winds are named for Santa Ana Canyon in Orange County, CA.

Credit: NOAA/NWS

Fall Foliage and Climate Change

Autumn is a season well known for its colorful foliage. Driven by the combination of sunlight, temperature, and precipitation, local displays vary from year to year. However, as the climate changes, so too will this familiar natural phenomenon.

As daylight hours decrease in the fall, there is less sunlight available to power photosynthesis – the chemical process that provides nutrients to trees by converting carbon dioxide and water into glucose, which is consumed by the tree and oxygen, which is released. This, in combination with falling temperatures, tells a tree to start preparing for winter.

To do this, a tree turns off its food producers by slowly corking the connection between leaf-stems and its branches.  This blocks the movement of sugars from the leaves to the tree as well as the flow of water from the roots to the leaves.  As a result, the leaves stop producing chlorophyll, the agent of photosynthesis and the reason for the green color of summer foliage.  As the green fades, other chemicals that have been present in the leaves all along begin to show.  These include xanthophyll and carotene, which produce yellow and orange leaves, respectively. Red to purplish colors are the result of anthocyanin, a chemical produced as a result any remaining sugars trapped in a leaf.

The change of leaf color happens every year, but the timing and duration of the displays are largely dependent on temperature and rainfall. Dry, sunny days and cool nights are the ideal recipe for beautiful fall foliage. Warmer and wetter conditions, on the other hand tend to delay the color change. However, extreme conditions, such as high heat, frost, excessive rain, or drought, can be a source of stress for trees and cause the colors to change early and the leaves to fall off faster.

As our climate changes, so too will displays of fall foliage. With warmer and wetter conditions forecast for the northeast, autumn colors are expected to peak later and disappear sooner. While there will still be variability from year to year, the fall foliage season in general is expected to get shorter. Furthermore, with the increasing probability of extreme weather events, such as storms with heavy rain, leaves could be swept from trees, effectively ending the season in a single day.

These changes will have more than an aesthetic affect. They are sure to have an impact on the multi-billion-dollar a year leaf-peeping ecotourism industry in several states.

Credit: Climate Central

Weather and Art: Rainworks

Rainy days can sometimes make people feel sad or depressed. This is what inspired artist Peregrine Church to create Rainworks – artwork activated by rain. His goal, he says, is “to give people a reason to smile on a rainy day”.

Based in Seattle, a city known for precipitation, he uses a super-hydrophobic spray to create images and sayings on concrete surfaces that are only visible when wet. As concrete gets wet, it gets darker. However, the areas covered in the waterproof coating stay dry and therefore lighter in color. This contrast allows the images and sayings to be visible to passersby.

Essentially street art, his first piece in 2014 was written on a city sidewalk and said “Stay Dry Out There”. He was soon joined his friend by Xack Fischer in creating Rainworks across the Emerald City.

In 2016, they started selling their specially formulated spray online. They also offer tutorials on their website to help people create their own Rainworks around the world. The spray according to the artists, is eco-friendly and biodegrades over the course of 2 to 4 months.

To date, more than 200 Rainworks have been created across five continents. You can find their locations (and add your own) on the Rainworks map.

A Rainwork in Yokohama, Japan. Image Credit: Rainworks Gallery

NYC Monthly Weather Summary: October 2018

October had a split personality in New York City this year. It started off unseasonably warm, but then temperatures plunged dramatically in the middle of the month and remained mostly below average until Halloween. Highs ranged from a balmy 80°F to a brisk 50°F. But in the end, these extremes balanced each other out. The city’s mean temperature for the month was 57.7°F, which is only 0.8°F above average.

In terms of precipitation, the city was fairly dry. Overall, 3.59 inches of rain was measured in Central Park. Of this total, 35% fell in single day during the first nor’easter of the season. On average, the Big Apple gets 4.40 inches of rain for month. This October also marked first month since June that the city received below average rainfall.

Credit: The Weather Gamut

Weather Lingo: Indian Summer

Autumn is a season known for colorful leaves and falling temperatures. Every once in a while, however, summer warmth makes a resurgence. When this happens, it is often dubbed “Indian Summer”.

This weather phenomenon, according to the NWS glossary, is defined as “an unseasonably warm period near the middle of autumn, usually following a substantial period of cool weather.”  In the northeastern US, it is generally associated with an area of high pressure to the south that ushers warm air northward.

In popular use since the 18th century, the exact origins of the term are a bit foggy. One of the more reasonable explanations behind this unique phrase suggests a connection to when Native Americans began their hunting season, but no one knows for sure.

In other parts of the world, this summer-like weather goes by a variety of different names. In Europe, a number of countries associate the unusual warmth with the nearest saint’s day. It is known as “St. Luke’s Little Summer” if it develops in October or a “St. Martin’s Summer” if it occurs in November. In temperate parts of South America, it is simply known as “Veranico” (little summer).

The timing and intensity of these autumn warm spells vary from year to year. Nevertheless, when they do occur, they usually only last a few days. So, as we inevitably move toward winter, enjoy them while you can.

Fall foliage. Credit: Melissa Fleming

Flashback Facts: Sixth Anniversary of Hurricane Sandy

Today marks the sixth anniversary of Superstorm Sandy. Here is a look back at some of the facts from that historic storm.

  • Sandy was the largest hurricane to form in the Atlantic basin. Its tropical storm force winds spanned 900 miles in diameter.
  • Impacts from Sandy were felt across 24 states, from Florida to Maine and as far inland as Michigan.
  • The most severe damage occurred in New York and New Jersey.
  • The storm surge at The Battery in NYC reached a new record high of 13.88 feet, flooding the streets, tunnels, and subways of lower Manhattan.
  • Sandy was responsible for 72 deaths in the US. Of those, 44 were in NYC and 24 were in the city’s hard hit borough of Staten Island.
  • More than 8 million people across 21 states lost power because of the storm.
  • Sandy caused more than $70 billion in damage.
  • It was the fourth costliest storm in US history after Katrina, Harvey, and Maria.

Superstorm Sandy. Credit: NOAA