ESM 6. Summary of advantages and disadvantages of different chamber types in the
Antarctic with respect to climate change scenarios. + or – indicate positive and negative
chamber type effects, respectively, in relation to a climate change scenario, +/- indicates that
the chamber effects is neutral or not applicable; + & - indicates chambers had contrasting
effects at different sites, nd: no data available. The last column provides suggestions to
overcome artefacts inherent to passive warming chambers and to improve simulating climate
change scenarios, although these may not be appropriate for all Antarctic field sites.
Climate change scenario
Warming
Events
Closed
Ventilated
OTC
Affected by
Alternatives
Summer
+
+
+
Radiation
Active warming
Autumn
+&−
−
+
Radiation and Snow
+&−
−
+
Snow
Spring
+&−
−
+&−
Snow
Active warming snow fence
OTC – snow
fence
Snow removal active warming
Winter
Night
−
−
+&−
Min temp.
Active warming
High temp.
+
+
+
Size of chamber
Minimize
extremes by using
OTC/Ventilated
chambers
Low temp.
+&−
+
−
Snow
Freeze-thaw
+&−
+&−
−
Snow
Dependent on
seasonality and
location
Snow
Accumulation
Spring melt
−
+/−
−
+/−
+
−
Type of chamber
Warming
Moisture
Rel. humidity
+
+/−
−
Evaporation
Soil moisture
+
nd
−
Evaporation
Depends on
cloudiness
−
−
−
Snow and season
PAR
OTC - snow fence
Shovelling active warming
Reduced as a
result of warming
Active warming