We are FINALLY turning the corner to Spring!

I don't know about you, but this winter has felt like it's gone on forever!  Where I live in SE Idaho, it's been dark, gray and COLD!  In fact, it's been so cold that the average high temperature in my town was 5o below normal, and the average low temperatures were even lower than that.  And we've had snow, snow, SNOW!  The snow at the top of my driveway (where snow gets tossed from the driveway and sidewalk) is nearly 6-feet tall!  So, whenever there is a sign of Spring, or at least Spring to come, it's cause to celebrate!  And that news came today from the far north...the Arctic Ocean.  

According to the National Snow and Ice Data Center, it looks like we have finally turned the corner from this year's maximum sea ice extent, and we may be headed back toward summer.

On top of that, I'm currently visiting family in Montana, and the melt here appears to be on!  This doesn't mean that it won't snow again...it probably will...but it does my heart so much good to see temperatures above freezing, melt water dripping down icicles, and puddles of water here and there during midday.  Plus, I've started hearing black-capped chickadees calling.  These are non-migratory birds, but they don't start calling until they are ready to start seeking out mates...and this means Springtime!

I say bring it on!  We have had snow on the ground constantly since before Thanksgiving where I live, and I'll be happy to see grass (albeit brown) again!     

Holy cow! The 2013 Arctic sea ice melt is accelerating like crazy!

I know I just posted on the Arctic Ocean sea ice melt, but, well, that was three days ago.  And three days ago it looked like an acceleration of sea ice melt might have been on the way, but I'd say that now it's official!  Look at the difference between the 1981-2010 baseline trend and the observed sea ice melt between the latter half of June and July 4th.  Wow!

I did a little math, and here's what I came up with.

On June 21st the historical baseline (1981-2010) showed sea ice extent at about 11.4 million km2 and 10.55 million km2 on July 4th.  That's a difference of 850,000 km2 of sea ice, or a melt rate of about 65,400 km2 of sea ice per day.

By comparison, the observed time period between June 21st and July 4th 2013 showed a sea ice extent of 11.1 million km2 on June 21st and an extent of 9.6 million km2 on July 4th.  That's a difference of 1.5 million km2 over that time period for a daily sea ice melt rate of about 115,400 km2 per day.

The observed melt rate for 2013 over the past two weeks or so is therefore nearly double the baseline melt rate for the same time period.  It's doubtful that this melt rate can be maintained for long, but the next few weeks will give us a good indication about whether the 2012 sea ice minimum extent record is in jeopardy. That is, if the current sea ice melt rate will be sustained, at least over the short term.

So, it's true, things are really starting to warm up in the Arctic.

Stay tuned...it's going to be an interesting summer!

Time to check in on the Arctic Ocean summer sea ice melt - 1 July 2013

It's been a while since I posted anything about what's happening in the Arctic Ocean.  In a word, the summer 2013 sea ice melt is "on".  So far this spring/summer, sea ice cover has declined from a winter maximum ice extent of just over 15 million km2 down to 10.5 million km2 as of yesterday (6-30-2013).

The maps below shows that sea ice melt is progressing much faster than the 1981-2010 average in Hudson Bay, the Barents Sea, Baffin Bay, and other areas around the Canadian Archipelago.  Sea ice melt in the Bering and Chukchi Seas are right on the historical average.

The graph below courtesy of NSIDC.org shows the relationship between the 2013 Spring/Summer melt and that of the 1981-2010 average and the 2012 all time record low sea ice melt.  The current melt is currently about midway between the historic average melt and the record melt for this time of year.  The rate of sea ice melt has really increased (as indicated by the steep downward turn in the blue line on the graph below) over the past week or so.  The rate of sea ice melt will really have to speed up, though, if it's going to have a chance of catching last year's record pace. 

If you follow these kinds of data on a regular basis, like I do, you might be surprised to see the current rate of sea ice melt is as close as it is to the historic rate of sea ice melt.  That's because NSIDC recently updated their baseline data for comparisons from a 22-year average (1979-2000) to a 30 year average (1981-2010), since that is standard practice for baselines whenever possible.  You can read more about that change by clicking this link: http://nsidc.org/arcticseaicenews/2013/06/updating-the-sea-ice-baseline/.  FYI, the NSIDC made this change on June 18, 2013.

So as of now, the 2013 sea ice melt is not threatening to break last year's record minimum sea ice extent.  But the only way to know what is going to happen is to be patient and keep checking back.

Have a great summer, but I hope that not too much sea ice melts!

What's going on in the Arctic? The winter sea ice freeze is on, but Arctic sea ice cover still 1 million km2 below historical averages

 It's been quite a while since I gave you an update on what's happening in the Arctic.

First of all, the Arctic Oscillation shifted recently from its Positive Phase to its Negative Phase; it has been mostly in the Positive Phase since the 1970s .  During the Positive Phase there is a large low pressure region dominating the Arctic, but during the Negative Phase there is a large high pressure system there.  This switch means that masses of cold Arctic air are more likely to push south and perhaps stay longer than they used to.  This is especially true for western North American.  This also helps explain the ice-box conditions we have been experiencing lately in the mountain west.

In other news, the Arctic Ocean sea ice freeze is well under way.  After the record ice melt of the summer of 2013, climatologists are keeping an interested eye on 2013's freeze up.  As the map below from the NSIDC.org shows, sea ice extent is at or sightly above normal in the Bering Sea and beyond the Kamchat peninsula.  At the same time, it is well below historical averages east of Scandinavia and south of Greenland.

If you recall, the Bering Sea produced above average sea ice coverage last year, and the lower than average sea ice in east of Greenland also lagged behind historical averages.

Though sea ice production and sea ice extent are still rising - as is to be expected this time of year - current sea ice extent is about 1 million km2 below historic averages (see the graph below from the NSIDC.org) 

FYI - The last time sea ice cover reached or exceeded the historic average for this time of year was in 1998 - yep, 15 years ago.  Every year since then, mid-January sea ice extent has been below average.  The take home message is that the Arctic continues to warm, and that sea ice extent continues to decline (on average) as the years go by.

North and South - Climate change and sea ice in the Arctic and in the Antarctic

Record sea ice melting in the Arctic Ocean receives a lot of attention from the media - as far as climate change news goes - but you don't hear that much about what is happening in the Antarctic.

First of all, a quick reminder about sea ice in the Arctic Ocean:

Sea ice melt in the Arctic Ocean in 2012 smashed the previous record by 750,000 km2.  The map below shows the observed sea ice extent in Sept 2012 (white area) compared to the 1979-2000 average extent (pink line)  Wow!  

Sea ice extent is defined as the area of the sea with at least 15% sea ice cover.  The graph below shows the Arctic sea ice extent for the years 2007-2012 and the 1979-2000 average.  Sea ice melt for all individual years shown (2007-2012) have minimum sea ice extents that are significantly (statistically) less than the 1979-2000 average (dark gray line; lighter gray area is + 2 standard deviations around the 1979-2000 average).    The bottom line for the Arctic is that it is warming significantly, and much faster than even the fastest climate models developed to date.

Ok, let's take a look at what's happening in the Antarctic:

The map below shows the Antarctic maximum sea ice extent (white area) for 2012 compared to the 1979-2000 average sea ice extent (orange line).  2012 sea ice extent in the Arctic set a new sea ice maximum record.  The graph below the map shows the sea ice extent for 2012 compared to the 1979-2000 average.

The graph below shows average sea ice extent for the month of Sept for 1979-2000 and for selected individual years.  Interestingly sea ice extent is increasing on average around Antarctica. When we look at data of sea ice cover in recent years in the Antarctic we see that 2006, 2007, 2011, and 2012 all had higher than average sea ice extent maxima but only 2006 and 2012 maximum extents were statistically higher (different) than the 1979-2000 average. With that being said, sea ice extent did exceed the + 2 standard deviation range in 2006 and 2012.  So, what is going on in the Antarctic that is leading to increased sea ice cover?

A report by scientists at the National Snow and Ice Data Center explains very nicely what is happening with sea ice extent in the south (http://nsidc.org/arcticseaicenews/2012/10/poles-apart-a-record-breaking-summer-and-winter/).

Here's a brief summary of their report together with some additional information to increase clarity:

1. Temperatures are warming in the Antarctic, just not as fast as in the Arctic (the NSIDC cites references you can refer to if you want more info on this.)
2. Warming of the Pacific Ocean and ozone depletion over Antarctica combine to strengthen circumpolar winds.
3. The strongest of these circumpolar winds blows east to west, and Coriolis Effect causes these winds to deflect to the left (north).  
4. The northerly flow of air around most of Antarctica causes sea ice to be pushed farther north than usual, spreading it out and increasing sea ice extent (remember, sea ice extent = 15% ice cover or more)

It would be very interesting to know whether the total amount of sea ice being formed in the Antarctic is increasing or decreasing.  All we know right now is how the ice that is being formed is being dispersed.

In summary:

Sea ice extent around Antarctica is increasing, but it is not increasing because it is getting colder.  It is increasing because winds blowing toward the north are dispersing sea ice farther away from the Antarctic coastline than usual.  Don't forget that sea ice formation in the Antarctic winter is followed by nearly 100% sea ice melt in the Antarctic summer - this is different than in the Arctic where multiple-year sea ice has historically accumulated.  

2012 Arctic Sea Ice Melt Shatters 2007 Record

Arctic sea ice extent -  A NEW RECORD MINIMUM

On 19 September the National Snow and Ice Data Center (NSIDC) released a preliminary report stating that the 2012 minimum sea ice extent in the Arctic was probably reached on 16 September 2012.  On that date the sea ice extent was 3.41 million km2.  That sea ice extent smashed the previous record minimum sea ice extent from 2007 by 760,000 km2.

The map below shows the sea ice extent on 9/16/2012 when it was at its minimum (white area).  The orange lines show the 1979-2000 average for sea ice extent.

What percent of sea ice cover remained of the historical 1979-2000 average at the end of this year's melt season?  Just over 51%.  That's right, the Arctic sea ice was nearly half gone at the end of the melt season.

Again, some people might argue that the sea ice extent minimum might have been a fluke random event, but that is looking less and less likely.  When we look at the past several years' sea ice minimum data they ALL fall below the 1979-2000 average.  The graph below shows the sea ice minimum extents for all the years 2007-2012.  The likelihood of this many years of sea ice minima below the average by random chance alone is just 1.56%.

And this table shows the actual sea ice extent data:

To wrap things up, "Is the climate change house on fire?" Should we be alarmed?  Look at the data and reach your own conclusion - and these data are just the tip of the iceberg.

Is the house on fire? Indications of climate change - 2012

I'm not an alarmist, but there are times to be alarmed - like when your house is on fire, or when you see the headlong approach of unswerving headlights.

When it comes to global climate, is the house on fire?

Record-settting number of high temperature records

The most recent data I could find on daily temperature records in the USA was from July 2012.  According to the National Climate Data Center, there were 23,283 new record high temperatures set across the United States from Jan-July 2012.

There are also some other troubling data and scenarios out there.

In mid-July a compelling article on climate change and current weather and climate patterns by Bill McKibben appeared in Rolling Stone Magazine.  You can read it in its entirety by clicking the link below.  

http://www.rollingstone.com/politics/news/global-warmings-terrifying-new-math-20120719

Building on data presented in that article we are now entering the 329th consecutive month with average temperatures above the 20th century average.  Yes, you read that right...329th month...that's nearly 27.5 years where EVERY month's average was above the 1900-1999 average temperature.  Now it is expected that any set of data from a natural system would include variability - year to year rainfall totals, temperature fluctuations, your heart rate, your annual body mass fluctuations, etc.  But when we see over 27 years of monthly average temperature data above the average of that for an entire century of temperature readings, we should probably sit up and think about what's going on.

If temperature fluctuations were behaving completely randomly, with no long-term temperature increase or decrease, we would predict that a given month's average temperature has a 50% chance (probability = 0.5) of being above average.  The chances of two consecutive months being above average would be 0.5 x 0.5 = 0.25 (= a 25% chance of happening by random chance alone).  So, what are the odds of observing 329 consecutive months with average temperatures above the 1900-1999 average temperature by random chance alone?  to get the answer to this question you need to multiply 0.5 by itself 329 times.  The answer is, according to the Rolling Stone article 3.7 x 10^-99.  That means that there is a 0.00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000037% chance of that happening by random chance alone.  That's such a small likelihood of happening that it's time to look for things that could be driving that other than random chance.

The prime suspect?  A trend of global climate change, i.e., global warming.

The total global average temperature hasn't increased all that much so far in the past 100 years or so...only 0.8oC.  And if we are seeing significant changes with only this small change in global temperature, what could happen when we reach 2oC?  - the projected limit that we could reach without incurring MAJOR global environmental and ecological effects?

BTW, climate models suggest that the atmosphere-ocean-earth system may be able to accommodate the emission of another 595 gigatons of CO2 into the atmosphere before we reach the 2oC mark.  But guess what?  The cumulative proven reserves of fossil fuels currently controlled by energy companies and countries with nationalized mining and extraction = 2,795 gigatons of fossil fuel.  That's just the fossil fuel that we know about.  That's 5x the total we can emit before hitting the 2oC mark.

Are there other indicators are there that climate is shifting?  Check out some of my other postings.

Record sea ice melt season reduces sea ice extent to only about 50% of its historical average

It's nearly the middle of September, the traditional end of the sea ice melt season in the Arctic Ocean.  The rate of sea ice melt has slowed over the past few days, perhaps signaling the beginning of the end of the Arctic Ocean sea ice melt season for 2012, but it's not completely done yet, and it's been a crazy summer in the Arctic!

Do you see what I see?  The extent of sea ice cover in the Arctic Ocean is WAY smaller now than the 1979-2000 average (orange lines) with only ~51% of the 1979-2000 average sea ice cover remaining today.

Consider this...

The average sea ice cover (extent) in the Arctic from 1979-2000 was about 6.7 million square kilometers.  Right now there is only about 3.45 million square kilometers of sea ice in the Arctic (as shown above).  The area of ice that is MISSING is shown on the map below.  Sea ice extent has NEVER been this low.

How does this compare to the previous sea ice melt record?  The previous sea ice melt record was in 2007.  The dark gray line on the graph below shows the 1979-2000 average sea ice cover.  The dashed green line shows the sea ice cover during 2007, and the blue line shows sea ice cover during 2012.  The 2012 ice melt smashed the 2007 record, with over 750,000 km2 more sea ice melting than in 2007.

Interestingly, the high amount of sea ice melt in 2007 was largely the result of an unusual Arctic weather year.  It had huge high pressure regions over large areas of the polar north, and lots and lots of sunshine, which meant lots of sea ice melting.  In 2012 however weather conditions did not appear to be set up to produce lots of sea ice melt.  There was a major cyclonic low pressure system that produced lots of cloud cover.  And that combined with associated winds normally slows sea ice melt.  But not this year.  It has just apparently gotten too warm overall in the Arctic for that kind of weather system to slow sea ice melt as much as it used to.

Maybe the sea ice melt in 2007 and 2012 were just statistical outliers.  I would have considered that as a possibility...until I saw the data for sea ice in the Arctic for the years between 2007 and 2012.

The graph below shows the sea ice cover data for the years 2007-2012 plus the 1979-2000 average.  An outlier is an observation that falls well outside of the observed long term trend.  What we see when we look at the data is that every year since 2007, and others not shown here, all fall well outside the 1979-2000 average.  But because there are getting to be so many years outside that average they collectively no longer can really be considered outliers.  Instead, they are possibly representing a new trend.

I just read an extremely interesting paper on what is and has been going on in the Arctic with respect to sea ice.  I recommend it highly if you are seriously interested in this topic.

• Stroeve, J. C., et al. 2012. The Arctic's rapidly shrinking sea ice cover: a research synthesis. Climate Change 110:1005-1027 DOI 10:1007/s10585-011-0101-1

Here is a link to a PDF file containing that paper: 

https://arcus.org/files/projects/supplemental/674/stroeve_etal_seaice_synthesis_2011.pdf

One of the things I found most compelling in Stroeve's article was the analysis of sea ice extent over the last 30+ years.  The conclusion is that the rate of sea ice loss is no longer linear.  Annual sea ice extents are dropping faster over the past decade than during previous decades.  The upper graph shows the rate of sea ice loss 1979-1998 in blue, and the rate of sea ice loss 1999-2010 in red.  The significant difference in these rates of sea ice loss is worth noting.  Stroeve's paper refers to models that suggest that the Arctic could become ice free in the summer as soon as 30 years from now.    

On the heels of this year's record sea ice melt, however, some climatologists are starting to suggest the possibility of a summer free of ice in the Arctic as soon as 10 years from now.  Yow!

Are you kidding me!? Arctic sea ice melt is already at a near record level and still going strong

In 2007 the rate and extent of sea ice melt shocked the world of climate scientists.  That year an unusual set of weather events combined to produce a record sea ice melt in the Arctic Ocean.  This year, 2012, that record is almost certainly going to be broken, if not shattered.  What makes this VERY unusual is that the recent conditions in the Arctic, including an Arctic cyclonic storm, normally produce slower sea ice melt conditions, not the record-pace conditions observed over the past several weeks.

The National Snow and Ice Data Center and NASA show that as of yesterday (8-23-2012) the sea ice extent in the Arctic Ocean is already at near record levels. 

This map shows the current area of the Arctic Ocean covered by at least 15% sea ice as of 8-23.

If you follow my blog you've certainly seen maps like this before.  The white area shows sea ice cover, while the orange line shows the historical average (1979-2000) sea ice cover for this date.  As you can see, the amount of sea ice currently existing in the Arctic is WAY below average, and it has been for the past several years. 

What makes this year different, however, is the rate and extent of sea ice melt - it's going crazy!

Normally the Arctic reaches maximum sea ice melt sometime in mid to late September.  The graph below shows some interesting things.  The dark gray line shows the historical rate of Arctic sea ice melt (1979-2000).  The light gray area aound that line shows + 2 standard deviations (i.e., the range that contains 95% of all sea ice extent observations during that 1979-2000 time period).  The dashed green line shows the pattern of sea ice melt during the previous record year, 2007.  The blue line shows the pattern of sea ice melt this year, 2012. 

As you can see, the sea ice extent in the Arctic is already within a hair's breadth of setting a new sea ice melt record.  That this would happen is not a surprise to climate scientists anywhere...what IS a surprise, though, is how early we reached this mark this year.  We are still anywhere from two to three weeks from the date when we observe the maximum sea ice melt for a given year. 

As for the record for this date, the sea ice melt for 2012 is somewhere between 500,000 km2 and 750,000 km2 greater (that's that much less ice) than in the previous record year of 2007!  Only time will tell now by how much the old record will be broken, but if this year's pattern holds it could be more than a record-breaking year, it could be a record-smashing year.

I'll keep you posted as the melt season progresses.

Have we passed a tipping point? 2012 Arctic sea ice melt is going like mad!

I don't have long, but I just want to get this out there.  When I checked in with the state of the Arctic Ocean sea ice melt I was surprised and shocked to see that the sea ice extent is rapidly closing in on the record sea ice melt observed in 2007.  That the 2007 record would be broken eventually is not the surprising thing.  The  surprising thing is that we are still weeks away from the traditional sea ice minimum (1979-2000 data) and nearly a month from the 2007 sea ice minimum date near mid Sept.

Who knows how much sea ice cover we are likely to lose before mid-Sept?

By my rough calculations based on this map, the 1979-2000 baseline sea ice extent for this date is 7.75 million square kilometers, the previous record for this date (in 2007) was about 5.3 million square kilometers, and the current observed sea ice extent is about 4.8 million square kilometers!  That's half a million square kilometers of sea ice LESS than we observed during the previous record set in 2007.

The 2012 data represent only one year's observation, and as such does not constitute  trend, but the rapidity of this year's melt, together with an Arctic cyclonic storm that normally tends to slow sea ice melt that instead accelerated it, gives me reason for concern.  (For more info on this, visit http://nsidc.org/arcticseaicenews/).

North America has had record heat through the spring and summer of 2012, a massive Greenland ice sheet has been reported that is well beyond anything previously observed, and eastern Europe and other regions of the world also report much warmer than average temperatures.

Unless there is a drastic change in Arctic conditions in the next few days we will almost certainly see a new record sea ice melt in the Arctic Ocean.

The good news is that a recent report from the United States Energy Information Administration (http://www.eia.gov/todayinenergy/detail.cfm?id=7350) stated that national CO2 emissions through the early part of 2012 were down to the level of 1992 emissions - mainly due to power plants switching to available, cleaner burning natural gas.  Still, this concerns me, because with even this reduction we are seeing record temperatures, etc.  I am hopeful, though, that this trend of decreased emissions will continue and mitigate climate change, if possible.

So I pose the question, have we passed a tipping point?  Only time will tell...

Arctic sea ice is melting nearly twice as fast as usual for June

I know it's only been a little while since my last Arctic sea ice update.  Am I obsessed?  Maybe...but that doesn't really matter...what matters is that things are currently happening FAST in the Arctic.

According to the good folks at NASA and the National Snow and Ice Data Center (NSIDC.org), Arctic Ocean sea ice cover changed dramatically over the past few weeks.

How far ahead of the historic baseline rate of sea ice melt are we?  The map below (NSIDC.org) shows that ice melt near Alaska and eastern Russia is on track with the 1979-2000 averages, but sea ice melt is well ahead of schedule north of Scandinavia, around Svalbard, SW of Greenland, and in the Kara Sea (north of Russia).

The white area on the map shows the area of the Arctic Ocean that currently has at least 15% sea ice cover.  The orange lines show the 1979-2000 historical sea ice cover on June 20th.

The data on this graph (courtesy of the NSIDC.org, and adapted buy me [lines and arrows]), though, was a real eye opener.

Figure description: The arrows #1 show the difference in sea ice cover between the 1979-2000 average and the 2012 cover at the beginning of June 2012.  Arrow #3 shows the area melted during the first three weeks of June for the 1979-2000 average.  Arrow #4 shows the area melted during the first three weeks of 2012, and arrow #2 shows the difference between the area of sea ice at the end of the three week period in 1979-2000 versus the ice cover area in 2012.

Historically, sea ice cover decreased from about 12.8 million km2 to 11.75 million km2 between 1 and 20 June, for a daily rate of sea ice melt of about 52,500 km2/day (see arrow #3 above).  During the current year, however, sea ice cover decreased from 12.45 million km2 to 10.5 million km2 in the same time period, for a daily rate of sea ice melt of 97,500 km2/day (see arrow #4 above).

THIS MEANS THAT DURING THE PAST THREE WEEKS WE OBSERVED ARCTIC SEA ICE LOSS AT NEARLY DOUBLE THE HISTORIC RATE FOR THIS TIME PERIOD.

See the Table below for more data...if that sort of thing floats your boat...

	1979-2000 Avg.	2012	Difference
1 June sea ice cover	12,800,000 km2	12,450,000 km2	350,000 km2
20 June sea ice cover	11,750,000 km2	10,500,000 km2	1,250,000 km2
Total Difference	1,050,000 km2	1,950,000 km2	855,000 km2
Rate of sea ice loss	52,500 km2/day	97,500 km2/day

Does this mean that we are likely to see a new record sea ice melt in the Arctic IN 2012?  It's hard to say, since weather conditions have the biggest effect on the rate of sea ice loss. We are, however, currently seeing record sea ice melt for June (so far), but not by much - see the graph below (NSIDC.org).  The sea ice extent for this time period in 2010 and 2011 is similar, thought slightly higher than are seeing this year.  If the 2012 ice melt stays on its current pace, there's a very good chance we could set a new record minimum sea ice extent (=sea ice melt) in the Arctic by September 2012.

It is important to note that sea ice can melt, reform, and get blown around, affecting the total area of the Arctic Ocean covered by sea ice.  Only the coming days and weeks will determine whether we will see a new sea ice melt record.

Don't get me wrong...I get the impression that some people think that I LIKE that Arctic sea ice is melting.  Nothing could be farther from the truth.  I don't like it, but I don't reject valid observations just because I may not like what they show, and because this is something that is happening that can affect the entire global climate, I feel compelled to share what I know about it.

What can we do about the situation in the Arctic?

While I believe that every little bit helps, and that individual choices can have an impact, and at the risk sounding a bit of gloom, it is possible that we may be past the point where individual action will make a significant difference.  I personally believe that we have reached a point where we must have governments pass stronger regulatory legislation limiting greenhouse gas emissions in order to make any meaningful progress toward any large-scale mitigation of climate change.

Here's hoping that at least the US Congress can get its act together and get to work on some meaningful environmental legislation!  Please, oh please, oh please!

"Canary in a Coal Mine" - Arctic Sea Ice

The spring Arctic Ocean sea ice melt is on!

Scientific predictions, observations, and climate models all lead to the conclusion that signs and effects of global warming will be most extreme near the north pole.  I saw some data this morning that made me sit up and take notice.

We are now in the middle of the most rapid sea ice melt of the year.  That's not the news.  The news is that the most recent data from NASA satellites and the National Snow and Ice Data Center (nsidc.org) show a notable drop in the percentage of the Arctic Ocean and nearby waters over the past few days.

Now a few days do not a trend make, but it is worth keeping an eye on!

This map (courtesy nsidc.org) shows two things.  1) It shows orange lines that indicate the historical average limit of sea ice cover in the Arctic Ocean between 1979 and 2000 for this date, and 2) the white area shows the actual sea ice cover for this date.

Just in case nsidc.org isn't one of your favorite web sites, and you don't routinely follow what's going on in the Arctic (I mean, what normal person does?), here's the scoop.  During the winter of 2011-12 there was a larger than average coverage of sea ice in the Bering Sea (west of Alaska and north of the Aleutian Islands) and it hung around longer than usual.  Today's map shows that the Bering Sea ice is breaking up - FAST!  Also, there is quite a bit of open water showing up north of central Canada and central Russia.  So, why the big news?

If you take a look at the graph below (also courtesy of nsidc.org), you will see the historical average amount of sea ice cover (1979-2000 - dark gray line), the area containing 95% of all historical observations (1979-2000), the current extent of sea ice cover for 2012 (blue line), and the extent of sea ice cover in 2007 - the year we observed the lowest sea ice extent ever (green dashed line).

OK, so what!?

The sea ice cover for 2012 fell easily within the normal range for historical sea ice cover all spring...until now.  During the past few days the sea ice extent has dropped out of the average range, and even below the 2007 extent.

Does this mean we will see record sea ice melt in the Arctic this year?  There's no way to tell at this point, because wind and weather conditions work together to determine the rate of ice melt and where the ice is blown.  But, these data show that we should keep an eye on the Arctic.  Why?  The overall sea ice cover has taken a short-term dip in total cover.  That may be temporary or it may be the beginning of a rapid melt.  Only time will tell on that one.

Why do I follow what's happening in the Arctic Ocean?  The Arctic is the Earth's climate "Canary in a Coal Mine".  Coal miners used to take canaries with them into the mines.  As long as the canaries sang and were healthy, they knew the air was OK.  But when a canary keeled over, passing out or dying, the miners knew it was time to get out.  This is because the canaries were more sensitive to air quality changes than humans.  Similarly, the Arctic is more sensitive to climate change than other areas of the globe, so when we see changes there - and we ARE seeing changes there, it's time to take notice and make changes to mitigate the problem.

What changes are we seeing?  For one, both winter and summer sea ice cover in the Arctic has been dropping significantly for the past 30+ years!

This graph (courtesy nsidc.org) shows the average sea ice cover for the month of May between 1979 and 2012.  While there is quite a bit of noise (year to year up and down) in the data, the long-term trend clearly shows that there is on average less sea ice in the Arctic in the month of May in 2012 than there was 30 years ago.  The slope showing the overall trend is statistically significant.

By the way, if noise in the data concerns you, you need to realize that EVERY natural system contains noise in the data.  This includes everything from local and global average temperatures to your own heart rate.  But if you collect data long enough, and scientists have, trends, if they exist in the data, will become apparent.  The trend in the Arctic is that it is getting warmer up there, and as a result the sea ice cover is dropping year to year.

In other words, the canaries are having a hard time singing.  They may be having a hard time breathing.

So what's happening with the Arctic Ocean melt, May 2012?

The annual Spring-Summer Arctic Ocean sea ice melt is well under way.  Like the past several years, the sea ice extent is below the historical average, though by the end of April the ice extent was still the greatest we've seen for this time of year since 2001.  Even so the NSIDC reported that the rate of ice loss is 2.6% per decade.  In other words...there's less ice up there than there used to be at this time of year, and every year there's getting to be less and less of the the floating white stuff!

The Arctic Ocean sea ice reached its maximum extent in mid to late March of this year.  The only time in the last five years when the sea ice extent was this large this late in the spring was in 2010 when it reached it's maximum in at the very end of March/very beginning of April.

Graph courtesy of the National Snow and Ice Data Center at the University of Colorado at Boulder. (NSIDC).  

The reason the sea ice extent is so large this year is that we have had colder than average conditions in the North Pacific.  The white area on the map below shows the extent of sea ice cover (at least 15% cover) as of 5/21/2012.  The orange lines show the 1979-2000 average extent of sea ice.  

Take a look at the Bering Sea, west of Alaska and north of the Aleutian Islands.  There's a LOT more ice there than usual.  The same thing is true for areas west of the the Kamchatka peninsula by coastal Russia and north of Japan.  In the north Atlantic, however, the melt is near normal by eastern Canada and Greenland.  It's ahead of normal, though, north of Scandinavia and northwest of the Kara Sea.  

I can't imagine that the ice in the north Pacific is going to last that much longer, but we'll just have to wait and see.

The take-home message?  The melt is underway, and though it's been slower than usual for May, it's still melting faster than average over all.

Approaching Arctic Ocean Annual Sea Ice Maximum Extent For 2012

One of my favorite climate-related web sites is the http://nsidc.org/. This is the site of the National Snow and Ice Data Center, housed at the University of Colorado, Boulder.  This is a great place to check on the state of snow and ice around the globe: the Arctic, the Antarctic, Greenland, mountain glaciers, etc.

The NSIDC posts a near-real time map and graph showing the current sea ice extent and recent trend of sea ice compared with a baseline average of the years 1979 through 2000.

Anyway, it's late February 2012, and according to the baseline data, this is the time of year that we are approaching maximum sea ice extent for the year.  The NSIDC defines an area to be "covered" by sea ice if a location has at least 15% of its surface area covered by sea ice.

Here is the most recent map showing sea ice cover, compared to the 1979-2000 baseline average:

The orange line on the map shows the baseline average extent of sea ice cover from the years 1979-2000. The white area shows the reported current extent of at least 15% sea ice cover based on satellite data provided by NASA.gov.  NSIDC scientists note that there is more ice than usual in the Bering Sea north of the Aleutian Islands - remember the challenge faced by residents of Nome, Alaska, earlier this winter when sea ice prevented shipping from reaching them?  At same time, just about everyplace else in the Arctic shows a lower sea ice extent than the historical baseline.  This is especially true in the Kara Sea and Arctic Ocean North of Scandinavia.

The figure below shows that we are fast approaching the annual sea ice maximum for 2012.  The maximum extent is usually reached sometime between mid-February and mid-March, so we are in the window.  Current Arctic sea ice extent (blue line) shows that the current sea ice extend is about 1.2 million square kilometers less than the historic baseline (dark gray line).  The current extent is also well below the + 2 standard deviation range (light gray zone) around the average baseline.  This means that yet again, the current sea ice extent is statistically significantly lower than the baseline.  And sea ice extent in the Arctic is comparable to the sea ice extent observed in 2006-2007 which produced the lowest summer sea ice extent on record.

Is this the record lowest extent for this date?  No.  The record for the lowest extent for this date goes to February 2011: last year - when we also saw the second lowest summer sea ice extent on record.

Does this mean that we will have a record low sea ice extent in Summer 2012?  No one knows.  The lowest sea ice extent is a product of not only a warming climate, but of prevailing short-term wind patterns and other weather conditions between now and then.  All we can really do is sit back and see what does happen.

So, until next time, keep an eye on the sky, the thermometer, and the ice.  Cheers!

Arctic sea ice melt the second largest on record

Starting in 1979, NASA started using satellites to monitor sea ice cover in Arctic Ocean. Each summer and fall climatologists and other interested people (like me) look forward with interest, and in some cases anxiety, to see how much of the sea ice melts during a given calendar year.  I, for one, have been following this annual cycle of sea ice production and melt for many years.

Scientists at the National Snow and Ice Data Center at the University of Colorado, Boulder, collect and analyze the NASA data and provide near real time updates on the status of Arctic sea ice, among lots of other things, throughout the year.  You can access their analysis as well as many fine sources of raw data at their website: http://nsidc.org/index.html

Sea ice extent is defined by the NSIDC as the total area that has at least 15% of sea ice cover.  Arctic sea ice floats.  This means that wind, wave, and current action together with other physical factors cause the sea ice to be constantly on the move.  It forms pressure ridges, and is constantly shifting.  In the Spring, temperatures increase and ice starts to melt, crack, and move.  If wind is particularly strong it will drive the melting ice together and expose larger areas of open water, especially between the shore and the ice pack.  When wind action is less powerful the ice remains more spread out and the 15% ice cover extends over a larger area.

The pink lines on the map below shows the 1979-2000 average sea ice extent (minimum of 15% ice cover).  The white area represents the area actually covered by at least 15% sea ice for the minimum sea ice extent for 2011.  The 2011minimum sea ice extent is significantly lower than the historical average.  (All images in this posting are courtesy of the NSIDC.)

This year the minimum sea ice extent is the second lowest ever recorded. 

The graph below compares the 2011 sea ice minimum extent to the 1979-2000 minimum sea ice extent (dark gray line) for the months of June-September.  The 1979-2000 line presents a baseline value that is useful for comparing annual sea ice extents to the baseline as well as to each other.  The lighter gray area surrounding the 1979-2000 average indicates two standard deviations of the historical data.  This means that observations that fall outside of that light gray area are considered to be statistically different than the baseline value for that date.  Sea ice extents for the years 2007, 2008, 2010, and 2011, are also included in this graph.

The 2011 sea ice minimum reached its minimum in early September, and only 2007 had a smaller sea ice minimum.

The graph below shows the minimum sea ice extend for the month of September from 1979-2011.  You will note that there is considerable variation around the blue line that represents the overall trend.  Sometimes people who do not understand how natural systems work will look at a single month's observation, such as 1992 or 1996, and jump to the conclusion that Earth's climate is not warming after all.  This is a faulty way to think about this kind of data.  A single observation does not always indicate the overall trend of the system.  It is important to realize that Earth's climate, like every natural system, contains variability around the prevailing trend.

OK, here's an example of what I'm talking about with respect to variation around a trend line.   One natural system that everyone is familiar with is heart rate.  Just about everyone knows how to take their pulse.  If you were to take your pulse a doze random times throughout the day, every day for a year those data would reveal two things: 1) your average heart rate; and 2) the amount of variability that exists in your heart rate.  Heart rate data can also reveal longer-range trends if monitoring continues and lifestyle changes.  For example, let's say that you have not been all that active for many years, but you decide to start exercising.  For lack of another option you start to jog, and then run on a regular basis, say 3-4x/week.  After doing this for several months you are consistently running 12-20 miles a week.  If you have been monitoring your heart rate all this time you will probably have seen a drop in your average heart rate as you have gotten in increasingly better shape.  That improvement would be reflected in a lowering average heart rate.  At the same time, you would still see lots of variability in heart rate each day, depending on what you are doing.  That's characteristic of any natural system.

Because there tends to be a lot of variability (also called noise) in the data collected on natural systems, such as Arctic sea ice extent, climatologists recommend that when considering climate trends a data set of at least 30 years, and longer when possible, is needed to identify overall trends.  Sadly, the overall trend of sea ice extent reveals a pattern of increasing sea ice melt.

When we consider differences in prevailing conditions in 2007, the year with the smallest measured sea ice extent, and 2011, the year with the second lowest extent, it's notable that the sea ice extent got as small as it did in 2011.  Why was 2011 a surprise?  The figure below shows the prevailing direction and rate of sea ice movement during the 2007 and 2011.  In 2007 there was a combination of strong prevailing winds and surface currents pushing the ice toward the Canadian/Greenland margins of the Arctic Ocean.  The size of the arrows represent the rate of ice movement (larger and longer arrows mean faster movement).  Remember that sea ice extent is measured in terms of 15% sea ice cover.  This means that there can be significant amounts of water between ice floes and still be included in the area of sea ice cover.  In 2007 forces jammed the ice together, minimizing the amount of water between ice floes, and produced a smaller sea ice extent than ever seen before or since (so far).  By comparison, if you look at the map of sea ice movement in 2011, there was sea ice movement, of course, but the rate and direction of movement was nothing like what was observed in 2007.  Wind and current action did not tend to compact ice in the central Arctic Ocean in 2011 the way they did in 2007.  This means that the low sea ice extent in 2011 is due to a higher amount of sea ice melt rather than due to sea ice compaction.  

The chart below shows the sea ice extents for September for the years 2007-2011 along with the 1979-2000 average.  While the annual sea ice extent data are interesting, showing the 2011 sea ice extent being only 300,000 km2 larger than that of the record minimum in 2007, the most significant result of the analysis to me is that the overall rate of decline in sea ice extent is decreasing significantly.  The overall rate of decline, based on a rolling 10-year average, is now at 12% per decade.  That's a lot!  These data support the explanation that climate change is happening, and that the Earth is warming.

Before I quit, I want to mention one last thing about scientists and what they do.  They do not want the climate to change, sea ice to melt, polar bears to be at risk, or other consequences of climate change to occur.  What they do want is to try to understand patterns and processes that explain what is happening.  This holds true for all scientists in all fields.  Though, like anyone, they may have pre-existing notions of what they think is happening, scientists are not content to stop there.  They are driven to make observations, analyze data, and then find out what is actually happening.  They then work to find the best explanations for the observations.  Lastly, once scientists have developed their best explanation about what is happening and why, they present that idea to the larger scientific community for critical review.  Only the best ideas, those supported by data and appropriate methods of analysis, survive that review.  

So, what's the bottom line here?  The Arctic polar region is warming, and quickly.  As for the Antarctic, that's a topic for another time.

(Originally posted 10-6-2011)

The Arctic Ocean continues to warm up...July 2011 had a record sea ice minimum

The amount of the Arctic Ocean covered by sea ice is the lowest on record for the month of July, according to The National Snow and Ice Data Center http://nsidc.org/arcticseaicenews/, located at the University of Colorado, Boulder.

This new sea ice minimum for the month of July exceeds even the previous record set in 2007, but toward the end of July the rate of sea ice melt slowed allowing the minimum from 2007 to once again surpass it.  If you look at the graph below (courtesy of the NSIDC.org) you can see the curves for 2007, the year with the standing record minimum sea ice for the year (dotted line) and the sea ice remaining for 2011 (the blue curve).    The sea ice amount for 2011 was less than in 2007 or any other previous year for which we have satellite data.  The rate of sea ice melt slowed at the end of July 2011, but during the past few days the rate of sea ice melt has picked up again.  Don't be surprised if we see a new sea ice minimum this September, but only weather conditions between now and then will determine that.

This map shows the 1979-2000 average sea ice for this time of year (pink lines) and the current amount of sea ice cover shown in white (also courtesy of NSIDC.org).  If you notice, sea ice melt is progressing particularly rapidly along the Russian and western Canadian and Alaskan shorelines.  It makes me wonder how long it will be this year before the NW passage will be ice free again this year.

This graph (courtesy of NSIDC.org) shows the sea ice extent for July 2011 compared to all previous years since 1979.  It shows clearly that it was a record low sea ice total for the month.  It's interesting that there are some people who look at data like these and say, for example, what happened in 2008!?  2009!?  Those were above the descending trend line?  And they conclude, based on one year's data that global warming is not happening.  In fact, years like 2008 and 2009 are to be expected.  We are, after all, looking at a natural trend, and there is always variability around any natural trend.  It's the overall trend of many years worth of data that need to be considered before a conclusion can be made.  In this case, the data all support the conclusion that we are looking at a trend of decreasing sea ice as the years pass.

In addition, climatologists have also been monitoring the age and thickness of sea ice, in addition to sea ice cover.  This graph shows the percent of sea ice cover on the left-hand image, and the age of ice on the right-hand image.  Scientists have discovered that there is less old (>2-3 year old ice) in the Arctic Ocean than in years past.  What this means is that younger, and therefore thinner ice melts faster than older, thicker ice.  And, since the NSIDC uses a 15% ice cover as a threshold for their measurements for their graphs, etc., this graph is particularly telling when it comes to assessing the status of ice cover in the Arctic Ocean.

If you look at the left-hand map, you will see that only a very small percentage of the Arctic Ocean still has 100% ice cover, and a significant area has only 15% or slightly more.  The prevailing winds and currents tend to cause ice to stack up along the north coasts of Greenland, Baffin Island, and other Canadian Arctic islands, so that is why the ice is thicker and older there.

I, for one, would not be a bit surprised if we saw a record or near record maximum sea ice melt this summer.

Interestingly, sea ice melt has no direct affect on sea levels.  When sea ice melts, it's just like ice cubes in your drink melting.  If you marked the level of fluid containing ice cubes in a glass, you will notice that there is no difference before the ice cubes melt and after they melt, because the total amount of water present in the glass does not change.  What we need to consider when it comes to sea level rise are two things, well, at least these two things: land ice/glacier melt (e.g., the Greenland ice cap), and thermal expansion of water.  As the world's oceans warm, the water becomes slightly less dense, and total volume increases.  We will also see increased evaporation, but the vast majority of evaporated sea water falls directly back on the ocean, so that's probably a negligible effect.

So...so what!?  It's still warming up in the Arctic.

Stay tuned!

(Originally posted 8-9-2011)

We could be in for a new record ice melt year in the Arctic Ocean

Originally posted 7-11-2011

This is a time series graph (see below) that shows the area of ice cover in the Arctic Ocean from the beginning of April through July 11, 2011.  As the legend in the graph indicates, the solid gray line represents the average ice cover (in millions of square Km) for all years between 1979 when satellite images of the summer Arctic first became available through 2000.  This constitutes a baseline average for comparison to the current extent of ice cover.  The lighter gray area bounding the dark gray line shows the amount of variability around the average.  This area is two standard deviations.  For those of you who have not studied statistics, a + 2 standard deviation range includes 95% of all observations in the data set (of observations between 1979-2000).  This also means that any observation that falls outside of that lighter gray area is considered to be significantly different than the baseline average.

OK, with that in mind, look at the graph below.  This graph shows the historical 1979-2000 average as well as the sea ice extent for 2007, the year that we had the maximum recent observed sea ice melt (the dashed green line), and the 2011 sea ice extent through July 11, 2011 (the blue line).  The 2011 line dipped below the 2007 line a few days ago, which, for this date, had the largest ice melt extent on record.  If this trend continues we will see another sea ice melt maximum.

(Graph courtesy of the National Snow and Ice Data Center - University of Colorado, Boulder, http://nsidc.org/)

In 2007 the maximum ice melt extent resulted in ice cover that was over 3 million square Km less than the historical average.  Some climatologists suggest that if the trend in sea ice melt continues we may see an ice-free Arctic Ocean in the next 50 years.  Of course, only time will tell on that prediction.

This link (see below), also from the NSIDC, will take you to the NSIDC website where you can view an animation that shows the maximum extent of ice melt from 1979 - 2009.  The white area in the animation represents ocean area that has at least 15% ice cover, and the pink line around the edge represents the 1979-2000 average extent of maximum summer melt.

http://nsidc.org/images/arcticseaicenews/20091005_Figure6.mov

For me, the conditions in the Arctic are one of the indicators, like a canary in a coal mine, of the status of climate shift on the planet.

The bottom line?  It's getting warmer out there.  Of course there is variability around the average, but that's the case for any natural system.  What you have to look at are trends.  And here's the trend in sea ice cover for the Month of June since 1979.  There are some observations above the trend line, and some below, but the overall trend shows decreasing ice cover over the past 30+ years.

(Graph courtesy of the National Snow and Ice Data Center, U Colorado, Boulder)

If you look at the graph above, you will see that for the month of June, 2011 had the 2nd largest ice melt on record, exceeded only by 2010, and 2007 is a close 3rd.  Whether we will see a new maximum ice melt by the end of the summer depends entirely on local weather conditions in the Arctic.

This graph, also from the NSIDC, shows the temperature anomalies, i.e., deviations from long-term averages for June, over the Arctic Ocean and nearby land masses.  Take a few minutes to familiarize yourself with this north polar view - it's not the way most of us are used to looking at the world.

You will see warmer than average temperatures over most of the Arctic Ocean, as well as Siberia and northern Greenland (2-5 oC warmer than the historical average for this time of year!).  Cooler than average conditions existed over Iceland and northern Canada east of Alaska and west of Hudson Bay (-1 to -2 oC cooler than the historical average for this time of year).  If these conditions persist, we could see another record ice-melt year.

(Graph courtesy of the National Snow and Ice Data Center, U. Colorado, Boulder.)

Well, this is something to think about!  I like to keep an eye on the Arctic