Robert Muir

Missing & remembering you Allan Riley - thank you for sharing your story Al, dad, gramps ... battle-of-the-atlantic.blogspot.com/2011/08/saint-… #RemembranceDay #LestWeForget #BattleoftheAtlantic

@therealmrbench @BonnieCrombie Often media & sometimes politicians get it wrong when it comes to what causes flooding - sometimes they do corrections when they look at the data: cityfloodmap.com/2019/06/?m=1 but often flooding is still blamed on more intense/frequent storms NOT observed in S.Ontario or Canada data

@BonnieCrombie That did not take long for the Liberals to start blaming the flooding on Mississauga on climate change.

My thoughts tonight are with communities in Mississauga and across our province that have been affected by the extreme weather conditions and flooding that struck this afternoon. We need urgent action to strengthen the climate resiliency of our province, from repairs to aging infrastructure and investments in decarbonizing our energy grid, to supports for homeowners and small businesses.

@therealmrbench @BonnieCrombie The climate in terms of extreme rainfall has not changed in 30 years based on @environmentca Engineering Climate Datasets for Southern Ontario, including Mississauga/ Pearson A climate station cityfloodmap.com/2023/05/southe…

@RogerPielkeJr @StephenMStrader Disappointing how the article got that concept wrong.

This is a misinterpretation of the "expanding bullseye" - a concept popularized by @StephenMStrader The weather event is the dart The "target" is the extent of societal development People are not moving into an expanding bullseye, people moving IS the expanding bullseye

🧵 This thread will take a detailed look at the @nytimes @dwallacewells article out today which really resets the apocalypse narrative that has come to dominate climate discourse Because the NYT & DWW as so influential in framing narratives, it is important to get things right

@RogerPielkeJr Thanks Roger. Similar trends in Canada based on long term @environmentca data: cityfloodmap.com/2022/05/maximu… ... some report on a shorter time periods starting in the late 1940's or 1970's and miss the earlier highs: thestar.com/politics/2022/… @TorontoStar #climatechange #extremeweather

What the media won't tell you about U.S. heat waves on The Honest Broker by Roger Pielke Jr. rogerpielkejr.substack.com/p/what-the-med…

@gavenuti @350Canada @JustinTrudeau Can @350Canada or @JustinTrudeau point to data showing wind or other extreme weather is hitting 'harder' and 'more often'? The @Canada in a Changing Climate Report did not have any analysis of extreme wind & said no evidence of observed more extreme rain (cityfloodmap.com/2019/06/canada…)

For decades scientists warned that extreme weather will hit harder & more often as fossil fuels heat the planet. Saturday was a terrifying example. It's not too late to change course but, by backing Big Oil, climate-delayers like @JustinTrudeau are setting us up for even worse.

@gavenuti @350Canada @JustinTrudeau Recent storm was a tragedy. But the NRC's recent benefit cost guideline for flood control shows that extreme rainfall has not been increasing across Canada (cityfloodmap.com/2022/02/nrc-na…) & @environmentca AHCCD data shows many city extreme temps not increasing (cityfloodmap.com/2022/05/maximu…

@mdhDuBois @arbol_y_agua Hi Marccus, here is a link: nrc-publications.canada.ca/eng/view/objec… - GSI costs are in Appendix F Annex F1. I'd think depending on local goals & benefits pursued, & varied site constraints (sanitary I&I/chlorides in WHPAs/shallow rock...) or opportunities, different approaches are preferred.

@RobertMuir_PEng Thanks for this Robert. Please share DOI. I agree that we can’t oversell GSI. At same time can’t throw baby out with bath water. That’s why my colleague @arbol_y_agua & I argue in a forthcoming piece on an intentional hybridized approach to urban stormwater mgmt.

@highlyanne @nanditabasu2 @StormWater_TO @NPR @EcoGreenQueen @PSUstormwater @mdhDuBois Not sure how GI can "take the top off big events" ? Sized to handle frequent small events GI gets filled in the rising limb of hydrographs & volume is not available for peak shaving. A better argument could be to reduce volumes cumulatively. Conveyance for big events is needed.

@highlyanne @NPR @EcoGreenQueen @PSUstormwater @mdhDuBois Unfortunately not a solution for most urban flooding challenges (50+ year old systems built to low standards) where conveyance/control of larger events is needed. Retrofitting large areas financially not sustainable (re lifecycle costs) - Ontario example: slideshare.net/RobertMuir3/co…

@AndrewSiffert @IPCC_CH Hi Andrew, the new @NRC_CNRC cost benefit guideline for flood control reviews rain intensities in Canada. Overall 100-year intensities decreased especially over short durations. In southern Ontario, since 1990 100-year intensities are overall unchanged: cityfloodmap.com/2022/02/nrc-na…

If anyone on #wxtwitter can show me proof climate change is impacting thunderstorms in the observations since 1990 please please let me know. The insurance industry wants to know. Until then I will stick to the @IPCC_CH findings of "low confidence".

True or False Statement: The raw SPC storm reports show a marked increase over time, which is partially due to population and reporting biases, but is also partially attributable to climate change (particularly post-1990)? 🤦‍♂️

@terencecorcoran Good point Terence. Flood peaks are up and down in Canada (tandfonline.com/doi/full/10.10…). @Canada 2021 National Issues report explains increased losses since the 1980's were due to 'growing exposure and rising asset values': cityfloodmap.com/2021/06/nation… #flooding #climatechange

As opposed to the fires and floods 100 years ago?

@RogerPielkeJr Unfortunate 'trickle-down effect' is that tools like climateatlas.ca from @environmentca use scenarios to guide other analysis, but with no consideration of the implausibility.

I am happy to hear from any IPCC contributor why this makes sense ⬇️

@gavenuti @ClimateReality The National Research Council of Canada's new cost-benefit guideline for flood control reviews trends and shows some regions have flat or decreasing trends: cityfloodmap.com/2022/02/nrc-na… - overall, 100-year storms are not more severe based on @environmentca Engineering Climate Datasets

Climate-intensified floods are becoming more frequent in Canada. The sooner leadership takes action to make Canadians more climate resilient, the better. nationalobserver.com/2022/02/16/new…

@vaughanvoice22 @treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @CNRC_NRC With climate change winter min, mean & max temps are up cityfloodmap.com/2017/12/univer… which increases winter infiltration (shorter frozen periods), increasing winter flow but lower spring peaks - points to lower risk (re peaks). @GuelphEng shows this for urban & rural systems too

@RobertMuir_PEng @treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @CNRC_NRC I’d have to look at the data. Antidotally, we had a lot of snow, a v. cold snap, more snow then a short warming w/ a lot of rain. It seems unlikely the ground would have had time to thaw to allow natural infiltration.

We are seeing significant damage to close to 100 homes in the Churchville neighbourhood of Brampton. Please follow @BEMOprepared for updates. @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics are all on the scene and assisting with evacuations. Stay safe!

@vaughanvoice22 @treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @CNRC_NRC Warmer winters can result in smaller spring peaks (lower flood risk) in melt-dominated systems - check out: tandfonline.com/doi/full/10.10… (Canada) or: slideshare.net/RobertMuir3/cl… (southern Ontario) - warmer means more winter infiltration & smaller snowpack = smaller peaks. Hope that helps

@RobertMuir_PEng @treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @CNRC_NRC Your not going to be able to convince me that flooding in February resulting from rainfall on frozen ground that reduces infiltration, likely impacted flow, which was further impacted by ice jams is NOT #ClimateChange. Plus development deficiencies.

@treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @vaughanvoice22 Homes have a variety of berms (dykes) flanking the Credit River, dating back decades due to the known risk (see streetview). When CHIC designed 407 ETR crossing downstream in the 1990's this risk was already well known.

@patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @RobertMuir_PEng @vaughanvoice22 Climate change at work? Are we going to take it more seriously when making our decisions on pop growth in ON? How many, where, when and if?

@treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @vaughanvoice22 Not climate change - its inadequate historical flood hazard management. This has been a high risk flood damage centre for a very long time. Existing berms protecting those properties have limits. Homes would not be built there (in a regulated floodway) under today's standards.

@vaughanvoice22 @treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics Recent National Research Council of Canada @CNRC_NRC guidelines on flood control cost-benefit analysis do not show changes in significant rainfall in southern Ontario: cityfloodmap.com/2022/02/nrc-na…. Impervious surfaces must be well-managed to avoid more risk: cityfloodmap.com/2020/10/town-o…

@treebeing @patrickbrownont @StormhunterTWN @BEMOprepared @regionofpeel @CityBrampton @BramptonFireES @PeelPolice @Peel_Paramedics @RobertMuir_PEng {Ice jams, significant rainfall, frozen ground, less infiltration = #ClimateChange} + {New development ⬇️decreases impervious surfaces =⬆️storm water run-off } = Flooding The flooding in the north is preferred #StopThe413 route on/near a floodplain. highway413.ca/wp-content/upl…

@RogerPielkeJr Good to know as many estimate extreme rain shifts w/ temperature. So why does @Canada plot RCP 8.5 as default scenario that paper shows "lies far outside the range of plausible scenarios", and has no option for more plausible SSP 3.4 range (@Canada calls RCP 4.5 'low carbon').

Seen our new paper? It's a good one rogerpielkejr.substack.com/p/is-the-world…