- Education and Science
Why Last Winter Was So Cold and Will It Continue This Year
Groundhog's day is long standing tradition that most of us barely pay attention to. In 2014, Punxsutawney Phil (a groundhog in Punxsutawney, PA where the biggest Groundhog Day celebration takes place each year) saw his shadow indicating six more weeks of winter. Anyone who has ever lived in Canada or in one of the northern states of the US knows it is a load of hogwash. Because no matter what Phil sees, for us there will always be six more weeks of winter. I have even seen it snow in May. At this point, we are used to having to batten down the hatches and not so patiently wait for our few short months of warm weather. However, the last winter few winters felt a bit different than the usual.
The last winter two winters were some of the coldest in history. The bitter seasons set record setting lows, crippled the Southwest, threatened crops with frost and deep freeze as far south as Florida, dropped snow in Cairo for the first time in over a hundred years, and left those of us in the Northern part of America and Canada praying to the weather Gods to please make it stop. I think we deserve the right to whine about the weather.
If your parents and or grandparents are anything like mine, however, then you're probably getting a daily reminder that sounds something like this: "it's not so bad, these are the kind of winters I grew up with," or "this is nothing compared to what I had to go through as a kid." These are the same people who probably survived the Blizzard of '77 and tell you epic tales of walking to and from school in ten feet of snow uphill, both ways.
There is some truth to their tales, though. Thanks to the polar vortex, last winter had an average temperature that was colder than usual, however, historically speaking, last winter really wasn't all that bad. It just felt cold because we were comparing it to the relatively mild winters of the most recent past.
But why have the last decade or so of winters been so warm, and what changed to make last winter so different?
Why Recent Winters Have Been So Warm
Excluding the last two years, the last few decades of winters have been the warmest on record, and businesses catering to winter recreational activities have suffered. Ski resorts had to increasingly make their own snow or risk shutting down, snowmobile sales were down, ice fishing became impossible because lakes and creeks weren't freezing over, and many businesses failed or risked bankruptcy because of it. I remember as a child a local business used to make ice castles and offered snowmobile rides over the lake, but in the last few years, it has not gotten cold enough to do either.
You can thank global warming for those mild winters, or global environmental change as I like to call it because as soon as you say the words global and warming together the claws come out. I'm not trying to make anyone believe global warming exists due to anthropogenic reasons, and maybe there are other reasons for this unprecedented rise in global temperatures. However, I will explain how global warming works in theory and let you decide for yourself.
The term, global warming, was first inadvertently coined by Wallace Broecker in 1975 in a paper he published entitled Climate Change: Are we on the Brink of a Pronounced Global Warming? Since then the topic has been hotly debated and as of 2009, just 51% of Americas believe in its existence.
The Green House Effect
An enhanced greenhouse effect is believed to be responsible for global environmental change and global warming. The greenhouse effect works just like, you guessed it, a greenhouse! Solar radiation (what the sun emits) passes through the atmosphere as ultra violet and visible light. The Earth absorbs this energy and reradiates it as infrared light, or heat. Most of the heat escapes back into space. Gases in the atmosphere, such as water vapor (H2O) and carbon dioxide (CO2), absorb the rest of the outgoing energy from Earth and reradiate it back towards Earth again causing the Earth’s atmosphere to warm. Without this process, the average annual temperature on Earth would be approximately 15°C cooler (and below freezing). Life as we know it would not be possible without the greenhouse effect.
Since pre-industrial times there has been an influx of greenhouse gases being emitted into the atmosphere, including carbon dioxide (CO2), methane (CH4), and nitrous oxide (NOx) which have increased approximately 30%, 145%, and 15% respectively. The excess gases in the atmosphere are believed to enhance the greenhouse effect by not only preventing infrared light from escaping into space, but also by absorbing more outgoing energy, leading to warmer surface temperatures. The global mean surface temperature has already increased about 0.3 to 0.6°C over the past decade (see figure to the right). Climate models project a further increase in temperature between 1 and 3.5°C over the next few decades. This change may seem small, but it can have a profound impact on Earth’s systems. As Wallace Broecker (a very famous environmental scientist) once said, “We have clear evidence that different parts of the earth's climate system are linked in very subtle yet dramatic ways.” A small change in one area will have rippling and devastating effects across the globe.
People can argue for ages on whether or not pollution is the cause for global warming or if it is natural. But the Earth is heating up, of that there is no doubt. And an increase in average temperature of the Earth would also mean an increase in average winter temperatures, hence warmer winters.
Everything You Need to Know About Solar Flares
How Solar Flares Effect the Climate
Global warming is not the only reason, however, for the relatively mild winters of the most recent past, the activity of the sun may have had an effect as well.
The sun goes through periodic changes in activity and appearance called a solar cycle. Currently we are on Cycle 24. Each cycle lasts about 11 years and has maximums and minimums. The maximums and minimums are defined by the number of sunspots.
During a solar maximum, the number of sunspots increases. Sunspots cause solar flares, which I am sure is a term you have all heard. A solar flare is what happens when magnetic energy built up in the sun's atmosphere suddenly releases, giving off more energy than a hydrogen bomb (times 10). When the sun flares, it emits energy across the entire spectrum sending high energy, charged particles hurtling to Earth. These particles often reach Earth within a day or two of being ejected from the Sun. Earth's magnetic field protects us from solar flares and prevents almost all of the energetic particle emissions from reaching the surface, however they can disrupt satellites and radio communications. If a coronal mass ejection takes place (which is an event that sends an even larger amount of material than a flare with more energy) there could be temporary loss of power over large regions when transformers and power stations are blown out due to the energetic particles. However, solar flares are also what gives us the stunningly beautiful auroras.
There has been an increase in solar activity over the last one hundred years. The early part of the 20th century saw a weak solar cycle, but that quickly changed. Up until recently, the sun was extremely lively, with very active maximums in both Cycle 22 and Cycle 23. The first, and biggest solar flare to date, was recorded in 1859 and since then the worst flares have all happened in the last 40 decades. For example, in 1989, approximately six million people were without power in Canada after a solar flare disrupted electric power transmission and in October, 2003 a flare happened that was so strong it topped out the measuring device. And this large flare was just part of a string of flares that lasted two weeks. The sun's strong activity, therefore, may have had short-term climate effects resulting in warmer winters.
However, with that said, there is no firm evidence linking solar activity with long-term climate effects. Despite the flares described above, the sun's activity has leveled off since the 70's, but the average temperature of the Earth has continued to increase. The sun's effect, is therefore, limited but still noteworthy.
Why Last Few Winters Were So Cold
Global environmental change explains the warming trend over the last decade, but it doesn't explain why the last two winters have set record lows in certain parts of America and Canada. Or does it?
According to the NOAA (National Oceanic and Atmospheric Administration) the average temperature of Jan 2014 in Western NY was a whopping 20°F, almost five degrees below normal. January was the coldest month that area saw in five years and tied for 26th coldest month in the 144 years of record. When compared to Jan 2013 and Jan 2012, Jan 2014 averaged 10 degrees colder. The month began with a cold arctic blast, and with a temperature of -5°F (before windchill is factored in) on Jan 7th, a new daily minimum record was set. So it's not just me, I have the numbers to prove winter sucks.
What about global warming, though? What happened? Well, global warming kept happening, that is what happened. Yes you read that right. The same thing that made the last decade or so of winters so warm is the very thing that is now making our winters colder than usual. But what changed?
Our climate did.
What is the Polar Vortex?
Our climate is changing slowly, but in profound ways. One of the biggest areas of change is the arctic. The arctic regions (the geographic poles) are warming up twice as fast as the rest of the Earth because of global warming and because that is where the biggest holes in the ozone are. Glaciers are melting and arctic animals, like the polar bear, are increasingly losing their home and becoming endangered. As a result, the temperature difference between the arctic regions and the mid latitudes (where the United States is) is decreasing. This temperature difference is what drives the polar vortex.
What is the polar vortex? Polar Vortex is a term that has only recently gained popularity in the media and public, but it is not a new phenomenon. There has been a polar vortex for as long as there has been an arctic region. However, its effects have only recently been able to make a profound difference here in the mid latitudes.
The polar vortex is a low pressure, semi-permanent weather system over the arctic regions of the Earth. There are two in the northern hemisphere, one centered over the Baffin Islands and a second over Siberia and another over the geographical South Pole. Weather in the northern hemisphere, as most of you know, moves from west to east because of the way the Earth spins. However the polar vortex remains over the arctic regions as a great mass of swirling freezing air that persistently circulates counter-clockwise. As the temperature difference between the area of the vortex and mid-latitudes decreases, the polar vortex weakens.
As a result of a weakening polar vortex, the movement of the air mass in the arctic begins to change. Rather than flow around the arctic in a circular manner, the movement of the cold air becomes wavier, bringing the mass further and further south (see the pictures above). If there is a high pressure weather system stalling over Greenland, a deep freeze could settle over the States for a week or more. This is the kind of weather pattern we saw in the early part of January.
I highly suggest watching the video below, it explains everything I just said about the polar vortex, only better.
But What About the Sun?
Solar Cycle 24 is only going to add to the problem of long, cold winters. Cycle 24, so far, has shown a decisive lack of sunspots. The maximum for Cycle 24 was in 2013 and it was the weakest maximum in almost a century. "Cycle 24 is different from recent cycles. You need to go back almost a century, to 1928, to find a cycle as weak as this," says Giuliana de Toma, a scientist at the National Center for Atmospheric Research's High Altitude Observatory (HAO).
As I said before, there is no evidence that solar flares have long-term climate effects. But consider this. Every heard of the little ice age, a period (or periods) of cooling between 1550 and 1850 AD? The Little Ice age is characterized by cold winters in Europe and North America. Entire farms and villages were destroyed by glaciers descending from mountains. In 1780, the NY harbor froze and if you wanted to (which not many probably wanted to) you could walk on the ice from Manhattan to Staten Island (when was the last time that happened?). Ports closed, ships became stuck or stranded in ice and snow fell in record sums burying towns and people under its frozen wrath. Humans adapted, inventing warmer clothing, changing the way they farmed, and creating better ways to warm their houses with fire. But the loss of life to famine and other weather related events was staggering.
Even China and Africa felt the bitter chill. Warm-weather crop farms, such as orange farms, in China were abandoned altogether and physical evidence of sediment cores and stalagmite growth suggest Africa was feeling the dip in temperatures during this time as well. Anyway you think of it, these long periods of cooling pretty much sucked for everyone.
Why am I telling you this? Because the Little Ice Age coincided with a long period of weak solar cycles. Between 1645–1715, which puts us somewhere in the middle of the Little Ice Age, there was a period of low solar activity known as the Maunder Minimum a time in the sun's cycle were sunspots were extremely rare. A significant cooling period between 1460 and 1550 also correlates to low activity of the sun, called the Spörer Minimum. Was low solar activity the only reason the Little Ice Age happened? No, but it certainly does give us something to think about in the coming years, especially since the next two cycles, Cycle 25 and 26, are expected to be just as weak, if not weaker than the current cycle. Though there is no real evidence to suggest that sun activity has any long-term climate effects, these weak solar cycles certainly won't help our situation and may help facilitate conditions leading to colder winters.
Are We Going to Have A Cold Winter? Will The Polar Vortex Return in 2015?
The NOAA (or National Oceanic and Atmospheric Administration) says last years bitter chill probably won't continue into this year, but a probably (and not a definitely) is not very reassuring. The main reason this winter is not forecast to be as bitter as last year is because of El Nino, which you can read about below. However, in the long run, we can expect this chilly trend to continue in the following years.
While decreased solar activity will decidedly play a role as stated earlier, our good old friend global warming will be the main culprit for this trend. Scientists and climate models don't expect any relief in the future, both agree that the average global temperature of the Earth will continue to rise which is bad news for us. As long as the arctic remains warmer than usual, the polar vortex will continue to be a problem for years to come. Unless the average global temperature suddenly decreases (which is extremely unlikely) we will continue to experience long periods of subzero temperatures and bone chilling winds as a result of the polar votex's waves reaching us.
Besides the polar vortex, there may be another reason why this trend will continue. Thanks to radioactive fallout from atomic bomb testing there was enough radioactive material in the oceans for Wallace Broecker (the very famous environmental scientist mentioned above) to use to map the currents of the Atlantic Ocean. During his study ,Wallace Broecker discovered that the currents in the Atlantic Ocean sort of work like a conveyor belt, bringing warm water up from the equator and sending cold water down to the equator. It explains why it rains so much in England. As the polar ice caps melt, though, the salt to water ratio in the ocean is thrown off. Why is this important? Because the ocean's currents are reliant upon the salt to water ratio. If that changes substantially, the currents change as well. Broecker theorized that if the polar ice caps continue to melt, the conveyor belt would stop altogether. If that stops, no more warm water from the equator means the temperatures will plummet in the regions of Northeast USA, Greenland, England, Ireland, etc. That really could send us into an actual Ice Age.
El Niño's Effect on Winter in the US in 2015-2016
Over the next few decades, colder winters will be the new normal, however Winter 2015 to 2016 may be the exception. Scientists predict that a strong El Niño may develop this year. El Niño is a weather phenomenon where the Pacific trade winds inexplicably falter not just a few days, but for weeks or months causing a band of warmer than usual ocean water to develop off the Pacific coast of South America, particularly around where Peru is.
As a result of El Niño, there are many serious and sometimes devastating changes to the climate. However, here in the northeastern part of the United States, far away from where El Niño is developing, it is not something we really have to worry about unlike Peru or California. El Niño does have the potential, though, to impact this year's winter.
If El Niño is a moderate or weak system, it can force the southern jet stream farther north than usual causing it to interact with the polar jet stream. That's bad for us because it means more snow than usual, something we really don't need more of.
If El Niño is a strong system, it can force the southern jet stream even farther north bringing with it some of that warm southern air to the northeast. For us that means relatively little snow compared to what we usually get and a warmer, milder winter.
Don't expect it to last, though. Even if next winter is warmer than this past winter, which is not a guarantee, as soon as the Pacific Ocean returns to normal and El Niño resides, unusually cold and snowy winters will return.