Uit het rapport van werkgroep I (over de wetenschappelijke basis).
Hoofdstuk 4, ,,Observations: Changes in Snow, Ice and Frozen Ground'':
,,In wide parts of the Himalaya most accumulation and ablation occur during summer (Fujita and Ageta, 2000), in the tropics ablation occurs year round and the seasonality in precipitation controls accumulation (Kaser and Osmaston, 2002).'' (4.5.1, p356)
,,Total mass balances are the integration of mean specific ass balances (which have a climate signal) over the existing glacier area. Consequently, the biggest mass losses and, thus, contributions to sea level rise are from Alaska with 0.11 mm yr–1 SLE from 1960/1961 to 1989/1990 and 0.24 mm yr–1 SLE from 1990/1991 to 2002/2003, the Arctic (0.09 and 0.19), and the high mountains of Asia (0.08 and 0.10) (Figure 4.15b).'' (4.5.2, p359)
,,Whereas glaciers in the Asian high mountains have generally shrunk at varying rates (Su and Shi, 2002; Ren et al., 2004; Solomina et al., 2004; Dyurgerov and Meier, 2005), several high glaciers in the central Karakoram are reported to have advanced and/or thickened at their tongues (Hewitt, 2005), probably due to enhanced precipitation.'' (4.5.3, p360)
Hoofdstuk 10, ,,Global Climate Projections'':
,,The global average sensitivity of G&IC surface mass balance to temperature is estimated by weighting the local sensitivities by land ice area in various regions. For a geographically and seasonally uniform rise in global temperature, Oerlemans and Fortuin (1992) derive a global average G&IC surface mass balance sensitivity of –0.40 m yr–1 °C–1, Dyurgerov and Meier (2000) –0.37 m yr–1 °C–1 (from observations), Braithwaite and Raper (2002) –0.41 m yr–1 °C–1 and Raper and Braithwaite (2005) –0.35 m yr–1 °C–1. Applying the scheme of Oerlemans (2001) and Oerlemans et al. (2006) worldwide gives a smaller value of –0.32 m yr–1 °C–1, the reduction being due to the modified treatment of albedo by Oerlemans (2001).''
Noot: prognoses voor de toekomstige afsmelt van de gletjers moet je dus verkrijgen door de verwachte opwarming te vermenigvuldigen met de gevoeligheidsfactor in mm/jaar/°C.
Hoofdstuk 11, ,,Regional Climate Projections'':
,,An RCM study by Gao et al. (2003b) indicates greater warming over the Plateau compared to surrounding areas, with the largest warming at highest altitudes, for example, over the Himalayas (see also Box 11.3). The higher temperature increase over high-altitude areas can be explained by the decrease in surface albedo associated with the melting of snow and ice (Giorgi et al., 1997). This phenomenon is found to different extents in some, although not all, of the MMD models, and it is visible in the multi-model mean changes, particularly in the winter (Figure 11.9).'' (11.4.3, p883)
Als je dus schrijft 'het IPCC zegt', of 'het IPCC verwacht', dan is het belangrijk te vernoemen uit welk rapport van welke werkgroep dat afkomstig is. Het IPCC spreekt zichzelf her en der ook tegen, wat ook nagenoeg onvermijdelijk is als je de omvang van het project bekijkt.
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