Dr Ann Rowan, Postdoctoral Research Fellow in the Department of Geography and Earth Sciences at Aberystwyth University answers questions about her work. She is giving a seminar tomorrow at Manchester Metropolitan University. It is free to attend and open to the public. It’s at 1pm. Room 2.10, Sandra Burslem Building. Manchester Metropolitan University
1) You’re “a glacial geologist interested in glacier–climate relationships in mountainous regions with active tectonics”. Is there a big academic community around that job description? What areas of t’planet do you guys study, besides the Himalayas?
There’s a lot of scientists interested in many different aspects of glaciers, but most of the modelling community has typically been looked at large polar ice sheets rather than alpine glaciers such as those in the Himalaya, New Zealand, the Rockies, the Andes and of course the European Alps. Since the publication of the 2007 IPCC assessment report which mistakenly stated that glaciers in the Himalaya would vanish by 2035 made us realise how little we knew about these glaciers, many more glaciologists, geologists and Quaternary scientists have been studying this region.
2) For the people who can’t get to your seminar next Tuesday, could you give a 100 word summary?
I’m going to be talking about the work my research group in Aberystwyth have been doing to try and develop 2-D glaciers models that we can use to predict how glaciers in Nepal will change over the next century or two. We are interested in how climate change over short time-scales (decades to centuries) affect the mass balance and ice flow of these glaciers, and what we can say about how individual glaciers behave. Many of the large Himalayan glaciers are covered with rock debris, which complicates their response to climate change and I’ll talk about how we are trying to quantify this. We’ve found that even using cutting-edge models, it’s difficult to describe how these glaciers will change with climate change, but we can quantify their sensitivity to climate. We think that its really important to collect detailed field data with which to validate numerical glacier models, and I’ll talk about our plans for fieldwork at the Khumbu Glacier in Nepal this spring. There will be lots of nice images of mountains and glaciers!
3) With respect to mountain glaciers, are the changes due to climate change happening quicker or slower than the models constructed in the 1990s and 2000s suggested?
Recent observations show that glaciers in the eastern Himalaya have lost mass more rapidly since the 1990s than earlier in the 20th Century, but its difficult for us to determine how quickly glaciers are changing as they respond to climate change more slowly than the climate change occurs. The glaciers we see today are still responding to the climate as it was 50 years ago or more. This lag between the climate changing and the glacier flowing into equilibrium with the climate is called the response time. On the other hand, models of glacier mass balance that don’t consider ice flow to equilibrium in this way show that even if no more climate change occurs from today, glaciers in the eastern Himalaya will lose up to 10% of their mass in future.
4) What are the human consequences of glacier changes likely to be in general?
Himalayan glaciers have been described as the “water towers of Asia” as they store water over the winter and release it each summer when the weather becomes warmer, feeding some of the biggest rivers on Earth—the Indus, the Ganges and the Bramaputra—which supply water to billions of people. Its possible that if they melt completely there will be droughts before the summer monsoon each year as it’s thought that this glacier melt bridges the gap between winter precipitation and the summer monsoon.
5) Given the way we are increasing our emissions, as a species, and the possibility of release of methane from permafrost, clathrates etc, will there be anything for glaciologists to study in 100 years?
That’s a good question! Climate change is not straightforward and over the next century we will see variations in how glaciers change in different parts of the world. At the moment, anthropogenic climate change has increased mean temperatures in the Northern Hemisphere which causes more snow to fall in winter in the Karakoram mountain range in Pakistan at the western end of the Himalaya. These Karakoram glaciers are actually getting larger while those to the east in India and Nepal are diminishing. This raises questions about how we might expect climate change to vary regionally in the future. Also, in 100 years, the polar ice sheets may have lost so much ice mass that parts of Greenland and Antarctic will resemble the Himalaya or the Alps, and there will be plenty of smaller glaciers for us to study where there were once large ice sheets.
6) Anything else you’d like to add?
Thanks for asking these questions and hope you enjoy my talk at MMU!