Compare the following photographs (in sets of two). Click to enlarge.
And a side by side.
Do you notice anything … unusual? These are examples of Glacial Repeat Photography. In each case someone happened to take a picture of a glacier at a point in the early 19th or 20th century, then later to illustrate the change in the size of the glacier someone else stood on that exact spot and repeated, or took another photo.
You can view more examples at the United States Geological Survey.
Ok, so what would logically cause the receding of glaciers worldwide? Kind of obvious isn’t it? Global warming. Now you may hear some naysayers say something to the effect that ‘While it’s true that some glaciers have been receding, others have been growing’. A blanket generalization at best. That’s because while a relative few are advancing due to the non-perfectly linear nature of climate change* on a large planet, by far the great majority have been receding, since warming is the major feature of anthopogenic, or human caused, climate change due to our burning of fossil fuels.
As of 2005 this was the situation:
The red vertical lines represent receding while the blue advancing glaciers.
“In 2005 there were 442 glaciers examined, 26 advancing, 18 stationary and 398 retreating.”
Here’s another chart of the worldwide picture:
And now? As of 2014 the loss continues.
The average mass balance of the glaciers with available long-term observation series around the world continues to be negative, with tentative figures indicating a further thickness reduction of 0.89 metres water equivalent (m w.e.) during the hydrological year 2013. The new data continues the global trend in strong ice loss over the past few decades and brings the cumulative average thickness loss of the reference glaciers since 1980 at 17.5 m w.e. (see Figures 1 and 2). All so far reported mass balance values given in Table 3, are tentative ~World Glacier Monitoring Service
From the University of Illinois a comparison picture of Arctic sea ice in 1980 and 2015.
So you decide. Is climate change real or not?
More on repeat photography here.
A climate change primer here.
*Which is why the term “climate change” is preferred over “global warming” – because climate is not always perfectly uniform planetwide. While the overall trend is warmer, there can be pockets of cooler areas and shifting weather patterns.