Observations on Arctic Sea Ice Challenge the Notion of Particularly Rapid Melting

I promised at the end of September, in my Finnish-language blog, to return to the topic of this year’s Arctic sea ice situation. At that time, it was already known—based on NSIDC’s daily measurements—that the annual minimum extent was the eleventh smallest in the history of the statistics. 

Then, at the beginning of October, the data on the average sea ice area for September was released. It appears at the endpoint of the curve below, under which only the points for the years 2007, 2016, 2019, and 2020 fall. Notably, this supports the view that the ice area has remained at the same level since 2007—that is, for 12 years already. The figure also clearly shows how, in September 2012, the ice area was distinctly smaller than in any other year.

This observation supports a recently published research report by Chinese scientists, according to which the phenomenon known as the North Atlantic Oscillation shifted from the lowest point of its negative phase in the early 2010s into a positive phase. As a result, the reduced heat and moisture, as well as the weakened downward longwave radiation, have led to a slowing of Arctic sea ice melting.

According to that study, however, this slowdown in melting would be only an intermediate stage, to be followed in the 2030s or 2040s by a rapid melting of northern sea ice—and subsequently, a series of environmental disasters around the world.

At this stage, of course, it is too early to take a position on that latter risk or its likelihood. Nevertheless, it can be stated that the slowdown in the melting of northern sea ice—at least for the time being—is a fact, one that seems at least partly to challenge the idea that the climate warming responsible for melting the ice is proceeding particularly rapidly in the Arctic region.

Previous thoughts on the same topic:
The Northern Sea Ice Area in 2024 Was Not the Smallest on Record
Can climate models predict the distribution of warming?
Correct minister, ridiculous facts

The Northern Sea Ice Area in 2024 Was Not the Smallest on Record

The year 2024 was apparently the warmest year in recorded temperature history. Therefore, I decided to examine the development of the northern sea ice area this year based on data collected by NASA's National Snow and Ice Data Center.

According to recent statistics, however, the northern polar ice defied my expectations. Its area was not the smallest on record but larger than in 2007, 2016, 2019, and 2020 as seen in the figure below. 

Additionally, its average area was not the smallest in any month of the measurement history. As I wrote earlier, in September, when the ice reaches its annual minimum area, it was the fourth smallest in recorded history.

This past December, however, the northern sea ice was the second smallest on record, so I am eagerly waiting to see what happens in January. Could it possibly shrink further than in previous years, giving hope for the opening of the Northeast Passage for maritime traffic?

Previous thoughts on the same topic:
Northern Sea Ice Area Has Not Responded to Exceptionally High Temperatures
Russia Pays the Price for Its Foolishness

Reevaluating Arctic Sea Ice Melt: A Closer Look at Trends and Predictions

Northern Sea Ice Area Has Not Responded to Exceptionally High Temperatures

The past October was extremely hot in many places (one, two, three examples), and for that reason, I checked NASA's NSIDC website to see if the northern sea ice might also have started melting. However, this was not the case; rather, it was the fifth largest in recorded history, as shown in the image below, which presents the polar ice area for each October over the years.

The October area of the northern sea ice was at its smallest in 2020, followed in order by 2007, 2016, and 2019. After these years comes the current year, 2024.

Thus, the area of northern sea ice has not responded to the exceptionally high temperatures on Earth’s surface—or, alternatively, there may be inaccuracies in the measurements of either the surface temperature or the ice area. Time will eventually reveal which explanation is correct.

In any case, throughout 2024, the northern sea ice area has not been the smallest on record for any month. In January, it ranked as the 24th smallest, in February the 14th smallest, in March the 25th smallest, in April the 27th smallest, in May the 24th smallest, and even in June it was the 11th smallest. After that, the melting rate of the ice accelerated compared to other years, and in July its area was the 5th smallest on record, in August the 2nd smallest, in September the 4th smallest, and in October the 5th smallest.

I won’t attempt to predict the coming months. Instead, I would like to point out to you - my esteemed readers - that the image above, which I generated based on NSIDC data seems to suggest that the melting of the ice, which began in the early 1990s, may have stabilized around 2007 and is now oscillating around a new equilibrium or is decreasing noticeably more slowly than in previous years.

I wrote earlier this year about a similar phenomenon in the July statistics, and indeed, it is also evident in the statistics for all other months. So, it remains to be seen how the ice area will develop over the last three months of this year.

Previous thoughts on the same topic:
Reevaluating Arctic Sea Ice Melt: A Closer Look at Trends and Predictions
Climate Model Predictions and the Reality of Arctic Sea Ice
Can climate models predict the distribution of warming?

Reevaluating Arctic Sea Ice Melt: A Closer Look at Trends and Predictions

According to a recent survey, as many as 70 percent of Finnish schoolchildren suffer from mental health issues. A significant cause of this is the news coverage related to climate change and the environment, which has driven even the most gifted young people into deep anxiety.

For this reason, I once again decided to analyze the melting of Arctic sea ice, which has been claimed to result in ice-free waters by the 2030s. Based on the statistics, I created the following image using data from the National Snow and Ice Data Center's dataset "All daily (single day and five-day trailing average) extent values in one file, updated daily," which officially begins in 1987 (prior to this, the dataset only contains data for every second day).

From this dataset, I extracted the minimum extent of Arctic ice for each year and plotted the following image, which shows the annual minimum extent of Arctic ice, its five-year moving average, and a linear trendline generated by Excel, which I manually extended across the entire chart.

From the red five-year moving average, it can be seen that the ice melt can be divided into three phases. From the start of the dataset until the mid-1990s, it was slow, but then accelerated for over a decade, reaching its minimum in 2013. After that, the melting slowed down again.

The black regression curve drawn on the chart for the entire dataset, however, shows that if the trend were to continue as it has in the recorded data, the Arctic sea ice would likely not be ice-free even by 2050. Therefore, the melting predicted by climate scientists for the 2030s must be based on other factors.

To understand this, I drew another image, in which I manually fitted a straight line that follows only the rapid melting phase in the middle of the dataset, aligning with the red five-year moving average. This appears as a green line in the image below.

As my esteemed reader will notice, this line corresponds to the scientific prediction of ice melt in the near future. Thus, it seems that the forecast in question—despite being mathematically and scientifically complex—is ultimately based on a development that would occur if the ice melt follows the trend from the late 1990s to 2013.

But what about the events in Arctic sea ice melting after 2013? To understand this, I performed a similar manual line fitting operation based on the post-2013 data. This is shown as a blue line in the diagram below.

As my esteemed reader will notice, this "data fit" also indicates a downward trend, but a very gradual one. And if this trend prevails in the Arctic, no living person today will witness an ice-free Arctic Ocean. Not even their children.

Therefore, I would hope that media coverage of climate change, and especially the melting of Arctic sea ice, would be less sensationalist and instead highlight the factors that suggest extreme views are unlikely to materialize. These also indicate that the models predicting rapid climate change still involve vast uncertainties, suggesting that humanity most likely has ample time to adapt to the ever-changing environment.

Previous thoughts on the same topic:
Climate Model Predictions and the Reality of Arctic Sea Ice
Can climate models predict the distribution of warming?
The area of Arctic sea ice was exceptionally large in January

 

Climate Model Predictions and the Reality of Arctic Sea Ice

Climate change caused by humans is expected to be particularly rapid in the Arctic region. As a result, the northern sea ice is expected to melt, perhaps as early as the next decade.

These predictions are based on such complex climate models that even researchers cannot fully understand them, let alone ordinary tax-paying citizens. Therefore, it is extremely interesting to follow the statistics on ice area development published by the National Snow & Ice Data Center (NSIDC).

NSIDC publishes ice area statistics monthly. And now the statistics for June are available, from which I drew the picture below.

As seen in the figure, the ice area in June has varied over the years, but it is not possible to say that it has decreased any further since 2007. It remains to be seen when its development will return to the downward trajectory predicted by climate models—or if it will at all.

In addition to the Arctic ice area, the NSIDC publishes daily statistics on ice extent, which differs from area in a similar way that the surface area of a slice of Swiss cheese including the holes differs from its area without the holes. According to this statistic, the ice extent yesterday was the fourteenth largest for that date in its measurement history.

I have been following these statistics for a long time and have been puzzled by the fact that they are rarely reported in the media aimed at the general public. However, I am sure that many readers would find following the melting of the northern sea ice quite interesting.

Aiempia ajatuksia samasta aihepiiristä:
Can climate models predict the distribution of warming?
The area of Arctic sea ice was exceptionally large in January
Does Arctic sea ice melt as atmospheric greenhouse gases increase?