Talk:Effects of climate change on the water cycle

Proposal to refocus this to Effects of climate change on water resources (withdrawn)

I am not sure what to think of this article. It seems to overlap a lot with others. Should it be integrated into effects of climate change? Or maybe it should be refocused and be called Effects of climate change on water resources or Effects of climate change on water security. I think those are the more pertinent issues, whereas the effects of climate change on the water cycle (i.e. precipitation, evaporation and alike) should probably be at effects of climate change. Pinging Daanstroeken. EMsmile (talk) 09:34, 1 April 2022 (UTC)

I am planning to refocus this article and to rename it to Effects of climate change on water security. Does anyone object? EMsmile (talk) 21:07, 7 April 2022 (UTC)

I am no longer pursuing this plan. Instead, I have added some climate change content to the article on water security. EMsmile (talk) 21:29, 26 April 2022 (UTC)

Building up this article with more content (September 2022)

I am beginning some serious work on this article today and over the next week or two to streamline it with water cycle and with effects of climate change. I see this article as a sub-article to water cycle and also as a sub-article to effects of climate change. I'll try to summarise the broad concepts in the two parent articles and put the more detailed scientific content here. Do you have any advice or suggestions for me? Which other Wikipedia article do I need to keep in mind, potentially? EMsmile (talk) 18:43, 29 September 2022 (UTC)

I've asked a content expert (Thian Y Gan, one of the IPCC AR 6 authors) for advice on the structure. Here is what he sent me: "Maybe you can consider some of the following section headings?

• Constraints on the global/ regional water cycle
• Thermodynamic constraints on atmospheric moisture fluxes and linkage to water cycles
• Large-scale changes in circulation patterns to global warming
• Local-scale land use changes and anthropogenic impact affecting the water cycle (my comment: I am not sure but I think this should be dealt with at water cycle as it's not an effect of climate change? I've already a new section for it there)
• Hydrological changes to ice and snow under climate warming
• Drivers to hydrologic extremes such as heavy precipitation, flooding, aridity and drought"

I am not sure what each of these topics mean but it's a good start. I shall investigate. EMsmile (talk) 18:47, 29 September 2022 (UTC)

I am still working on the right structure for this article. Looking at the chapter "The Changing Hydrological Cycle" in this book by Keven Trenberth, the structure is as follows:

10.1 The Global Water Cycle
10.2 The Surface Freshwater Flux 144
10.3 Climate Model Performance 147
10.4 The Changing Water Cycle 148
10.5 Extremes of Rain and Floods 151
10.6 Drought and Wildfires 153
10.7 Changes in Tropical Storms 155
10.8 Water, Climate, and Society 157

And here is how Chapter 8 (water cycle changes) of the AR 6 WG I report looks

8.1 Introduction
8.2 Why should we expect water cycle changes
8.3 How Is the Water Cycle Changing and Why?
8.4 What Are the Projected Water Cycle Changes?
8.5 What Are the Limits for Projecting Water Cycle Changes?
8.6 What Is the Potential for Abrupt Change?
8.7 Final remarks

Maybe we can come up with a similar structure for our article. EMsmile (talk) 08:32, 30 September 2022 (UTC)

Key statements to be included and explained

This was sent to me by Keven Trenberth. I'll work on integrating this into the article: "The main impacts of a warmer climate on global water cycle include the following:

• With warming, higher atmospheric temperatures increase the water holding capacity of the atmosphere by about 7 % per degree Celsius (e.g., Trenberth et al. 2003). (this statement we already have in the article)
• Over the ocean where there is ample water supply, the relative humidity remains about the same and hence the observed moisture goes up at about this rate: an increase in total column water vapor of about 4 % since the 1970s (Trenberth et al. 2007b).
• Over land the response depends on the moisture supply.
• With more heat in the Earth system, the evaporation is enhanced resulting in more precipitation. The rate of increase is estimated to be about 2 % per degree Celsius warming (Trenberth 2011).
• Locally this means increased potential evapotranspiration, and in dry areas this means drying and more intense and longer lasting droughts.
• Larger warming over land versus the ocean further changes monsoons.
• Precipitation occurs mainly from convergence of atmospheric moisture into the weather system producing the precipitation, and hence increased water vapor leads to more intense rains and snow, and potentially to more intense storms.
• More precipitation occurs as rain rather than snow.
• However, higher temperatures in winter over continents favor higher snowfalls.
• Snow pack melts quicker and sooner, leading to less snow pack in the spring.
• These conditions lead to earlier runoff and changes in peak streamflow. Hence, there is a risk of more extremes, such as floods and droughts."

Sources which can be used to substantiate this: Trenberth, K. E., 2011: Changes in precipitation with climate change. Climate Research, 47, 123-138. doi:10.3354/cr00953, Trenberth, K. E., and G. R. Asrar, 2014: Challenges and opportunities in water cycle research: WCRP contributions. Surveys in Geophys., 35, 515-532. doi 10.1007/s10712-012-9214-y EMsmile (talk) 09:01, 30 September 2022 (UTC)

Further information from Kevin that could be integrated (pinging User:ASRASR as he's currently working on this article): We could add this statement: "The regional changes vary: at high latitudes it is the average temperature that is increasing, while for the oceans and tropics it is in particular the rainfall and the water cycle where changes are observed.” Kevin wrote to me: "That is a sound statement but not sure where if it is stated anywhere in my papers. It is effectively stated in: Trenberth, K. E., and D. J. Shea, 2005: Relationships between precipitation and surface temperature. Geophys. Res. Lttrs., 32, L14703, doi:10.1029/2005GL022760 [PDF] and Trenberth, K. E., 2011: Changes in precipitation with climate change. Climate Research, 47, 123-138, doi: 10.3354/cr00953 [PDF] Similarly it is implicit in my book but not stated quite that way so succinctly. At high latitudes there is next to no moisture in the air: it is freeze dried whether over land or ocean or ice. Land vs ocean matters little as both are covered in ice. Land in lower latitudes is an exception because it depends on water availability: e.g. deserts. It never rains! So available excess energy goes into evaporation where moisture is available but increases with Clausius Clapeyron at rate of 7% per deg C temperature, which is what rules out the high latitudes." EMsmile (talk) 07:57, 4 July 2023 (UTC)

Care to use layman's language to help readers?

"Time-mean precipitation and evaporation as a function of latitude as simulated by an aqua-planet version of an atmospheric GCM (GFDL's AM2.1) with a homogeneous "slab-ocean" lower boundary (saturated surface with small heat capacity), forced by annual mean insolation." I just finished translating the article into Traditional Chinese, and had a hard time understanding the cited wordings, can anybody help? Thanks. ThomasYehYeh (talk) 23:32, 29 April 2023 (UTC)

Good point. I have deleted this image now with the justification being: too complex, root source link also seems to be broken. Quite old. EMsmile (talk) 08:14, 2 May 2023 (UTC)

Wiki Education assignment: ERTH 4303 Resources of the Earth

This article was the subject of a Wiki Education Foundation-supported course assignment, between 12 January 2024 and 10 April 2024. Further details are available on the course page. Student editor(s): Andrewglouchkow (article contribs). Peer reviewers: ToedToad, Ottawaotter2024.

— Assignment last updated by Spencerladner (talk) 20:17, 1 March 2024 (UTC)

Desertification

This article does not mention desertification due to climate change. Is this relevant to the effects of climate change on the water cycle? Jarble (talk) 23:21, 29 February 2024 (UTC)

Would agree that drylands undergoing desertification is in part an impact of climate change. See https://www.nature.com/articles/s41467-020-17710-7 Please make this addition including linking to https://en.wikipedia.org/wiki/Desertification Could go into the section on droughts https://en.wikipedia.org/wiki/Effects_of_climate_change_on_the_water_cycle#Droughts But since this is an excerpt it might best be mentioned here https://en.wikipedia.org/wiki/Effects_of_climate_change_on_the_water_cycle#Impacts_on_water_management_aspects ASRASR (talk) 00:24, 19 March 2024 (UTC)

Hi ASRASR that's a really useful paper from 2020. Easy to understand and compatibly licenced. I have copied some info from its abstract to the desertification article now, and brought it back to here by using an excerpt. More info could be taken from that paper to show the complexities, also with respect to the opposite trend (global greening). We could also take some of the figures. I'll put a note about that on the talk page of desertification as well. EMsmile (talk) 09:57, 9 April 2024 (UTC)

Please edit incrementally

Hi User:Andrewglouchkow, what happened here in this huge edit? Dumping so much text in one go makes it very difficult for other editors to follow what you have been doing. Please rather edit incrementally, one paragraph at a time, especially when you are an inexperienced editor. I can see that User:Kazamzam has already had to remove some of your content as it introduced repetition. EMsmile (talk) 09:27, 18 April 2024 (UTC)

I've decided to restore the old version before you (User:Andrewglouchkow) added all that new text. I am sure that some of your new content will be useful but it needs to be added incrementally and carefully. It almost feels like you didn't actually read the existing article. I can see e.g. in the lead that you had added a lot of repetition. The lead should be no longer than 500 words. You need to work with the existing content, not just add new content. EMsmile (talk) 10:09, 18 April 2024 (UTC)

@EMsmile - thank you for your edits on this. This user, and others, are part of a WikiEd class that focuses on the environment; unfortunately there have been a number of large edits made these editors that are detrimental to these articles. I believe this stems from these new/inexperienced editors effectively rewriting ("rewriting") the article, or at least large parts of it, from scratch in their sandboxes and then copying it to the body of the article. I'm working on identifying and fixing problems as I see them so you might see edits like these if you have other related pages on your watchlist. Much obliged for the helpful instructions above. Best, Kazamzam (talk) 11:40, 18 April 2024 (UTC)

Hi User: Kazamzam, thank you. This is really sad. Sad for the students because they put their efforts into the wrong type of editing, and their edits get reverted. And sad for the Wikipedia community because we have to now mop it all up. I am in theory all for student assignments but time and time again I get disappointed by most of it (very rarely it's excellent content). They hardly ever work on existing content but always insist on adding brand new content... Do you think we should alert the instructors of this particular course if it's a pattern with this course that you have also observed? EMsmile (talk) 15:58, 18 April 2024 (UTC)

@EMsmile - the instructor @JMungall has been quite responsive to concerns about student edits which is great but of course, this is one course for one semester from one university. I mentioned to JMungall how the WikiEd standard procedure is, in my opinion, detrimental to both the students-as-editors and to experienced editors but I'm limited on where to go from here because I'm not involved in WikiEd. One person to get involved might be @Ian (Wiki Ed) for ideas on how the process might be improved for everyone. Kazamzam (talk) 16:31, 18 April 2024 (UTC)

(we should probably move this to either your talk page or mine...)

Here's an idea: there's an instructor in Sweden (Olle Terenius) whose students are making far better edits than what I've seen come out of the most of the US university courses. His courses are not supported by WikiEd but the way he teaches the students obviously works. Perhaps a best practice guidance document could be created from his experiences? See his dashboard of courses.

Whether those US-based professors would follow such a guidance if it was presented to them is another question... I don't know what kind of guidance they get thus far from Wiki Ed.

There have been long discussions about student added content also in WikiProject Medicine, see for example their talk page here. EMsmile (talk) 16:52, 18 April 2024 (UTC)

Hi @EMsmile, @Kazamzam. I'm glad someone has finally reached out to me on this matter. I have always used the Wiki Ed package and their online training to get the students started, and having never received any feedback from mainstream Wikipedia editors I've never thought there was much of a problem. The students are told repeatedly to avoid copying entire articles in and to use the Talk pages but I see that they are not all getting this message or perhaps simply don't understand. Our students are often pretty clueless but with the right training and motivation I find that most of them are capable of good work. On the other hand some of them are simply lazy and looking to get credit for the minimum possible amount of attention to details - people like that are hard to work around but maybe keeping their efforts restricted to the sandbox would be helpful.

Upon reflection I'm realizing here that normally the people making edits on Wikipedia are a self-selected group of people who want to improve the transfer of knowledge (with or without personal axes to grind) but when I throw forty students in and tell them they need to do this to pass my course, I'm bringing in a set of editors with a different set of motivations that only partially intersect with those of all the other editors. Some will share your urges to make Wikipedia better, but some are just trying to get by without any sense of the importance of the project.

I want to make this work better next time (I'll probably only be doing this one more time, next winter, before I shuffle off into admin and ultimately retirement). I will follow up the links you've suggested and I'll look for more guidance from @Ian (Wiki Ed). It's too late to change the outcome this year (and to be fair, it wasn't all bad!) but the creation of a more comprehensive set of tutorials on the effective use of Talk pages, submission of proposals to Talk pages before editing on the main pages, and on establishing stricter guidelines for professors regarding the correction of work before it goes into the main pages, all might be helpful to my class next year and to others in my situation. I'll create those tutorial materials myself and try to share them with the Wiki Ed group, but input from people like yourselves will make my efforts a lot more useful. JMungall (talk) 18:18, 18 April 2024 (UTC)

Housekeeping: this discussion is now continuing on JMungall's talk page. EMsmile (talk) 20:39, 18 April 2024 (UTC)