It appears that glaciers on balance are shrinking and sea level are rising- they are directly related. If sea levels were to stop rising then we can assume that glaciers in total are increasing. But as far as I know since the end Little Ice Age sea levels have been rising:

"Most mountain glaciers worldwide have been retreating since the late 1800's, and global sea level has risen about 12 centimeters since then. As glaciers vary in size, they respond to changes in global and regional climates (such as warmer summers). The U.S. Geological Survey (USGS) studies the complex links among glacier variation, climate change, and global sea level.
Sea-level changes, especially in densely populated, low-lying coastal areas and on islands, have significant effects on human activities and facilities. The present volume of the Earth's glacier ice, if totally melted, represents about 80 meters in potential sea-level rise. About 200 meters is the range of sea-level changes that can be caused by water being frozen in glaciers during an ice age or melted during an interglacial epoch. For example, during the last glacial maximum, about 21,000 years ago, sea level is estimated to have been 125 meters lower than it is today. During a warmer climatic interval in the last interglacial period, about 125,000 years ago, sea level was about 6 meters higher than it is today; during an even warmer interval about 2.2 million years ago, sea level is estimated to have been 25 to 50 meters higher."
http://pubs.usgs.gov/fs/fs130-02/fs130-02.html

Here's a bit about Antarctic glaciers:
"Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level may severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet could cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). In spite of its importance, the mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is poorly known; it is not known for certain whether the ice sheet is growing or shrinking. In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic part of the Antarctic ice sheet is probably becoming thinner overall; although the western part is thickening, the northern part is thinning. Joughin and Tulaczyk (2002), based on analysis of ice-flow velocities derived from synthetic aperture radar, concluded that most of the Ross ice streams (ice streams on the east side of the Ross Ice Shelf) have a positive mass balance. The mass balance of the East Antarctic is unknown, but thought to be in near equilibrium."
http://pubs.usgs.gov/imap/2600/F/
More stuff you can read about glaciers:
http://www.glaciers.er.usgs.gov/html/web.html

Monbiot says:
"Like you, I am sceptical of the idea that we can simply replace our carbon-based economy with other forms of energy. The main effort has to be massively to reduce consumption. But if I am to answer your question, you will have to explain it to me. What do you mean when you say that wind turbines can't "provide us with a sustainable source of future energy"? Is wind about to run out? "
http://www.marklynas.org/wind/document/20.html

In other words Monbiot is an idiot.
Regarding Monbiot Guardian piece. I suspect that there could be a small chance [say 25%] that this fellow Bellamy is poking fun at Monbiot.
But in any case if Bellamy was serious then it's possible that he was wrong [but I couldn't find this april 16 article cited in article] if I were to assume this Monbiot character was accurately conveying what Bellamy wrote, I think that would a mistake because as I said Monboit is an idiot.