External Reading Flashcards
Who researched glacier decline globally for the early 21st Century?
Zemp et al., 2015
What did Zemp et al., 2015 suggest with regards to glacier mass decline?
That there has been unprecedented mass loss and a strong imbalance, which combined with climate change scenarios suggests that there will be further loss beyond historical precedent
Which indicators of climate change are important for assessing the impacts of glaciers on global sea level? (With Citation)
Length, area, volume and mass
Zemp et al., 2015
Who researched surging glaciers in Svalbard?
Boyle et al., 2000
What did Boyle et al., 2000 find out with regards to surging glaciers in Svalbard?
They found that long glaciers with steep slopes and young fine-grained sediment bases are most likely to be surge-type glaciers as this supports the switch between fast and slow flow
Who studied glacier and ice sheet change using the GRACE satellites?
Pritchard et al., 2010
What did Pritchard et al., 2010 find out with regards to net mass loss globally by using GRACE satellites?
That there have been advances in net mass loss in Greenland and the Gulf of Alaska
Who found by using satellites the strong summer melt on the Antarctic Peninsula is equivalent to ~70m/annum?
Pritchard et al., 2010
Who studied iceberg calving and glacial earthquakes?
Bauge et al., 2015
Who found that ~50% of Greenland’s mass loss occurs through iceberg calving?
Bauge et al., 2015
What are glacial earthquakes? (With Citation)
Globally detective seismic events that with remote sensing can allow for interpretation of calving processes in Greenland and Antarctica (Bauge et al., 2015)
Who researched water flow through temperate glaciers?
Fountain and Walder, 1998
What did Fountain and Walder, 1998 find with regards to water movement in temperate glaciers?
In the accumulation zone the flux of water to the interior varies slowly as firn stores water. In the ablation zone water fluxes depend on surface melt and rainfall. Englacial conduits are also supplied by the accumulation zone making them steady state features
Who studied Alpine Subglacial Hydrology and what did they find?
Hubbard and Neinow, 1997
They found that the size and shape of the subglacial flow pathways have a strong influence on the pressure and speed of water that meltwater passes through glaciers, which in turn influences glacier sliding velocity and BMW discharge
Who found that most of our glacier knowledge is based on temperate glaciers and that understanding polythermal glaciers is important in a warming climate?
Irvine-Fynn, 2011
Who studied Ice Sheet Hydrology in Greenland and what did they find?
Chu, 2014
They found that understanding the hydrology of Greenland is important because of a warming climate and the future contributions to global SLR. Remote sensing also revealed that there are land and marine terminating glaciers that have conduits underneath them.
How has our knowledge of the drainage system in evolved?
In the 1990s we knew that it evolves from increased meltwater and that transitions can occur from distributed to channelised. We then found that when water reaches the bed of ice sheets, speed up occurs. More recently we have found that the drainage system in Greenland evolves like a valley glacier does
Who used dye tracing in d’Arolla Switzerland and found that channelised system can evolve, which increases efficiency?
Neinow et al., 1996
Who used GPS on the Greenland Ice Sheet and found that water can reach the bed causing a runaway feedback?
Zwally et al., 2002
What is the Zwally effect?
An acceleration of the flow of marginal ice sheets and the ice within it due to the lubrication of the bed by meltwater percolating from the surface
Who used satellite data from the Greenland Ice Sheet and found that water can reach the bed rapidly via moulins as a result of supraglacial lake drainage?
Das et al., 2008
Who used radar from the Greenland Ice Sheet and found that mourns transit water to the bed and that they can persist for several seasons?
Catania and Neuman, 2010
Who used GPS on the Greenland Ice Sheet and demonstrated that there is speed up seasonally and that there are similarities with traditional valley glaciers on the Greenland Ice Sheet?
Bartholomew et al., 2010
Who used satellite data from the Greenland Ice Sheet and found that subglacial lake storage is an important consideration when looking at outburst events?
Willis et al., 2015
Who used GPS and Satellites on the Greenland Ice Sheet and found the opposite to the Zwally effect?
Tedstone et al., 2015
Who used dye and gas tracing and demonstrated seasonal drainage system evolution on the Greenland Ice Sheet?
Chandler et al., 2013
Who used Oxygen Isotopes and Field Investigations to give the first recorded outburst of water in Antarctica at the Casey Station?
Goodwin et al., 1988
Who has conducted the most recent review of our knowledge in Antarctica?
Ashmore and Bingham, 2014
What methods have been seen to be useful in studying Antarctic subglacial connections and by whom?
Radio-Echo Sounding (Wingham et al., 2006)
Satellites (Fricker et al., 2007)
How many subglacial lakes are there across the AIS and which is the largest? (With Citations)
More than 400 (Siegert et al., 2016)
Largest contains ~5,4000 cubic km of water (Wingham et al., 2006)
Who conducted the research at the Haut Glacier in d’Arolla which revealed the 3 glacier modes?
Tranter et al., 1997
Who found out that carbonate hydrolysis occurs before sulphide oxidation?
Tranter et al., 1997
Tranter et at., 1997 found a high S ratio in subglacial drainage waters, what were the 2 suggested reasons for this?
- Carbonate hydrolysis is occurring before sulphide oxidation
- CO2 in the subglacial environment may increase chemical weathering
Who said that areas with glaciers are good for studying rock-water interaction and why? (2 reasons)
Brown, 2002
- High Chemical Weathering Rates
- Low Anthropogenic Impacts
What did Brown (2002) find out about the characteristics of BMW quality?
It can provide information on key hydrological and hydrochemical processes in the subglacial environment
Who said that uncertainties remain regarding the role of meltwater and CO2 sequestration on G-IG timescales?
Brown, 2002
Who studied microbial life of the cryosphere?
Boetruis et al., 2015
What 2 types or organisms did Boetruis et al. (2015) find?
Photoautrophs where sunlight penetrates the ice
Chemoautotrophs where it is dark in the subglacial environment
Where is microbial life most abundant and what threatens it in the future? (With Citation)
The interface between ice and liquid
Threatened by a warming climate
(Boetruis et al., 2015)
What are the 2 key glacial ecosystems (with examples)? (With Citation)
- Supraglacial – bacteria, supraglacial streams, cryoconite holes
- Subglacial – bacteria, viruses and lakes
(Anesio et al., 2008)
What must be looked at when considering the impact of climate change on glaciers? (With Citation)
Surface and Internal Heat Balances
Anesio et al., 2008
Who studied the Greenland Ice Sheet as a Phosphorus Hotspot?
Hawkings et al., 2016
What % of bioavailable phosphorus to the Arctic Oceans comes from the Greenland Ice Sheet? (With Citation)
~15%
Hawkings et al., 2016
What are the 2 sources of P from the Greenland Ice Sheet? (With Citation)
Snow & Ice Melt
Hawkings et al., 2016
Who found that glaciers can efficiently transport Phosphorus to the coastal regions?
Hawkings et al., 2016
What did Hawkings et al., 2016 say was an important consideration based on the Phosphorus findings in Greenland?
The impacts of nutrient cycling during snowball Earth and on G-IG timescales
Who found that the ocean waters around major ice sheets are iron limited yet productive ecosystems?
Hawkings et al., 2014
What are labile iron fluxes from glacier meltwater comparable to? (With Citation)
Aeolian Dust Fluxes
Hawkings et al., 2014
Who said that glaciers can provide a vital link between terrestrial and aquatic carbon fluxes?
Hood et al., 2015
How much of a cumulative loss is due by 2050 due to climate change and how much Dissolved Organic Carbon does this equate to? (With Citation)
~15 Tg (10tothe12) = ~½ the annual flux of DOC from the Amazon River
(Hood et al., 2015)
What has a recent study found about the Larsen C Ice Shelf in Antarctica?
In the last 20 years, warming has caused 2 ice shelves to collapse (A in 1995 and B in 2002) and this third one (twice the size of Wales) is thinning and could face collapse. If it was to collapse glaciers could flow more quickly into the ocean, having significant impacts on global sea level. Threatened by warming ocean and atmosphere.
What have Rignot and Thomas (2002) found with regards to the mass balance of polar ice sheets?
Greenland Ice Sheet is losing mass to coastal thinning and the WAS is thinning in the West and thinning in the North with an overall thinning. The EAS has a small imbalance.
