cc: "'n.sheard@uea.ac.uk'" date: Thu, 30 Sep 1999 10:19:53 -0600 from: "Barrow,Elaine [Reg]" subject: comments on Canada brochure for WWF to: "'m.hulme@uea.ac.uk'" Mike, I've been through the Canada leaflet you sent me. I also circulated it to a couple of other people here at Environment Canada - I hope you don't mind, but I thought they may have some valuable comments as well. I realise that you are probably space limited and that you are trying to keep the text as simple as possible, so some of our comments may be more detailed than you want, but here they are anyway: p.1: Recent observed trends amend sentence to read: The annual mean temperature has increased by about 0.8degC since 1900, with 1998 being the warmest year this century - almost 2degC above the 1961-90 average. We would like to see a graphic of the greater warming in western Canada. If you want to pick on a particular year you could find relevant information in the Climate Trends and Variations Bulletin for Canada (http://www1.tor.ec.gc.ca/ccrm/bulletin). This currently shows the anomalies for this summer, but if you click on the CTVB archive button at the bottom of the page you can find graphics for earlier seasons. Last winter (listed as winter 1999) was interesting with a large warm anomaly in the north of western Canada. We think the most significant warming has occurred during the winter and spring seasons and not spring and summer, so you may want to check this. You are probably aware that national data for Canada including the north are very sparse prior to the 1940s and this has probably been accounted for in figure 1. Figure 1: caption: for or across Canada, but not over. Fill in missing values. Arctic sea ice: '.....Arctic summer melting season (Figure 2). The latter data, also derived from satellite monitoring, suggest a lengthening of the melt season...'. Amend last sentence: Although these data are for the Arctic as a whole, similar observations have been made in the Canadian Arctic region. Figure 2: It was suggested that you add statistical values to the best fit line, but this is probably too complicated for this leaflet. p.3: We found the text concerning carbon emissions and CO2 concentrations slightly confusing - particularly the decrease of 4% for B1, but an increase to 550 ppmv CO2 by 2100 for B1, so you might want to clarify this a bit. I think you should make mention that you use a simple climate model to combine emissions and climate sensitivity to obtain estimates of changes in global-mean temperature and sea level rise. The three people I circulated the leaflet to all wanted to know how you arrived at Table 1 from emissions and sensitivities. Changes in climate and sea level: Amend first sentence to: These four scenarios indicate increases in global-mean temperature of between 1.3degC and 4.6degC...... Since you say that the rise in sea level will be one of the most striking consequences of global warming it would be nice to include a graphic of this, i.e., a graph from MAGICC. Also in this section, why do you focus on cities in the US? If you are trying to make the point globally mention some other places such as Bangladesh and the Maldives, if not, mention some Canadian cities such as Vancouver or Charlottetown. The Canadians are very sensitive to always being compared to the US, so it's probably a good idea to mention Vancouver at least! p.4. Figure 3: colour code the lines to correspond to the scenarios or label them accordingly. Also, I would put the graphs side by side rather than on top of each other and make sure that the y-axis degC anomaly scales are the same for both, so that the exaggerated warming in Canada cf. global is immediately apparent. p.5. Future temperature change across Canada (not over). refer to the Canadian Arctic region rather than just the Canadian Arctic. If by referring to the Northwest Territories you mean north of 60degN, you should be aware that there is now a new territory within the Northwest Territory - Nunavut Territory (and Yukon Territory is over in the west), so you may want to refer to north of 60degN, rather than the NWT. Also, 'southern provinces' isn't really a term that would be recognised over here - southern Canada is where most of the population live so to say southern provinces is a bit strange (particularly since there are no provinces in the north, only territories), so you may want to say south of 60degN, or something similar. Figure 4: how is this pattern derived? At the beginning of the leaflet you say that you are using 7 GCMs, but we think you should say whether this pattern is derived from a single GCM expt. and say which one, or from combining all of them. It was pointed out that current trends and one of the experiments from CCCma indicate cooling in NE Canada. Also, most Canadians will be most interested in how the winter temperatures will change, rather than the annual mean, so it would be more useful to show winter and summer rather than the annual mean. Amend title to the figure to Annual Temperature Change. I think you should make it clear in the caption that it is simulated natural temperature variability and not actual. p.6. Future precipitation change across Canada (not over). First paragraph not completely clear, so we suggest the following amendment: GCM experiments indicate that annual precipitation increases across all of Canada in the future. This increase is largest over the Canadian Arctic region where winter precipitation increases by between 15 and 45% by the 2080s, depending on the scenario. South of 60degN (or in the provinces) winters become up to 25% wetter by the 2080s under the A2-high scenario. The only season which does not become uniformly wetter in Canada is the summer. Here, large areas of south-central British Columbia, central Alberta and northern Saskatchewan become drier during the summer season - in places up to 10% by the 2080s. Figure 5 - amend title to 2080s Precipitation Change and again make clear in the caption that it is simulated natural climate variability, rather than observed. Since you have shown winter and summer precip changes here, it would be more consistent to show winter and summer temperature changes in Figure 4, rather than annual mean, as suggested earlier. p.7 Climate change, the Canadian Arctic region and Biodiversity. You need to get this section checked by a biologist! Permafrost and forests - are you referring to the mean temperature isotherm? The thawing of the permafrost will have its greatest effects on infrastructure, i.e., roads and pipelines, but it may also affect the number of wetlands. As far as we know the Kodiak bear isn't in Canada - we have the grizzly, black, brown or polar bears. None of us had heard of the emperor goose, so I looked it up in the bird book you bought me as a leaving present and that indicated that the goose's range is the coasts of Alaska and the neighbouring bit of Russia down to the Aleutians - it's not actually in Canada. Amend: Fewer days of frost, as suggested by our scenarios, will therefore herald...... Fire outbreaks will also depend on the timing and amount of precipitation and you may also want to mention that fire is important for the health of the forest ecosystem and, in some cases, for forest regeneration. The Caribou and Polar Bear Change 'isolated nature of the Arctic' to 'marginal nature of the Arctic'. Mosquito populations are heavily reliant on the amount of standing water and precipitation - if there is no standing water for them to breed in, there won't be many mosquitoes. They aren't only dependent on temperature. Also they aren't the only serious insect pest affecting the caribou herds, so you may want to mention some more, e.g. black flies. Amend: Further north in Canada, a reduction in the area of Arctic sea ice, as a direct response to the rising temperatures, may result in the extinction of species such as the polar bear and the ringed seal. Polar bears will eat small mammals and berries, so although their diet may be limited they aren't really forced to fast. The Inuit are more reliant on seal hunting than polar bear hunting (in fact we're not sure if they even hunt polar bear - it is not one of their traditional targets - see http://www1.tor.ec.gc.ca/index_e.cfm and follow the regional green lane site links to prairie and northern region and the Arctic ecosystems for more information). Figure 6: distinguish the different scenarios by colour coding or labelling. p.8: It was suggested that you may want to put the climate model differences section before the future temperature and precipitation changes across Canada, or at least make clear that Figures 4 and 5 are derived from a single GCM (if they are) and that there is actually a range of possible futures. Figure 7: make clear that the natural climate variability is model-simulated and is actually an underestimate of the true natural variability. Also, change 'Plains' in heading to 'Prairies' since you refer to Prairies in the text. That's all! Hope you find them useful. TTFN Elaine Elaine Barrow Environment Canada - Regina Tel: 306 780 6049 elaine.barrow@ec.gc.ca