Talk:Effects of climate change

Scientific opinion on climate change impacts

In my view, this article should briefly discuss the range of scientific opinion on the impacts of climate change. Previously I suggested that this be added to scientific opinion on climate change, but I was unable to reach a consensus on that article's talk page.

In this article, my proposed addition would describe the main sources of information on climate change impacts (e.g., reports by the Intergovernmental Panel on Climate Change and statements by scientific bodies), as well as a general discussion of areas where there is a broad consensus and robust evidence, and other areas where there is less evidence and a lack of consensus (e.g., see [1]). Specific uncertainties can be covered in sub-articles.

Enescot (talk) 08:11, 30 March 2014 (UTC)

Either please provide a link to the earlier thread, or alternatively please elaborate how your proposal differs from what we have. NewsAndEventsGuy (talk) 12:03, 30 March 2014 (UTC)

My addition would be similar to Attribution of recent climate change#Scientific literature and opinion, where opinions are explicitly attributed to a particular source. I've already provided some examples of sources:

- The IPCC

- Other authoritative assessments [2] [3]

- Science academy statements, e.g., [4] [5]

- Regional [6] and national assessments [7].

Enescot (talk) 06:13, 8 April 2014 (UTC)

Not sure how I missed this, but apologies for not responding sooner. Article addition looks good to me, thanks for doing that. From the science side of the literature, can you think of any heavy hitters talking about cost & risk of acting today, versus cost & risk of delaying and acting tomorrow? NewsAndEventsGuy (talk) 09:27, 20 June 2014 (UTC)

Thanks for your response. As I'm sure you know, the recent IPCC Working Group II report [8] offers an assessment of policy responses to reduce climate change damages (Chapter 19, p46 onwards). The earlier IPCC assessments also provide summaries (AR4 WG3 Sections 3.5-3.6 [9]; TAR WG3 Section 10.4 [10]). PBL (2009) [11] is another useful summary. Enescot (talk) 02:54, 4 July 2014 (UTC)

I was thinking more along the lines of the cost of delaying mitigation. Something analogous the IEA report discussed in this Reuter's story "Cost of extra year's climate inaction $500 billion: IEA" Assuming we want to hold the line at any given amount of warming, one of the GW's effects is on the range of our options and speed with which they must be deployed.NewsAndEventsGuy (talk) 11:24, 4 July 2014 (UTC)

As I'm sure you know, this is discussed in the most recent IPCC Working Group 3 report. In my opinion, this issue needs to be considered in the context of other relevant articles, such as global warming, climate change mitigation, Avoiding dangerous climate change, and economics of global warming#Risk. In my opinion, the issue should only be mentioned briefly here, with reference made to other relevant articles, e.g.,:

"Many of the risks of climate change can be reduced by cutting anthropogenic greenhouse gas emissions (see: climate change mitigation). The negative impacts of climate change may also be reduced by adaptation measures, e.g., promoting socioeconomic development (main article: adaptation to global warming."

Enescot (talk) 07:37, 12 July 2014 (UTC)

Increasing food prices are one effect. Increasing cost to mitigate enough to hold the line at 2C is another. Your example sentences don't capture changes to the cost of mitigation. NewsAndEventsGuy (talk) 12:26, 12 July 2014 (UTC)

I've started a new thread to continue this discussion - Talk:Effects of global warming#Costs of delayed action. Enescot (talk) 06:39, 26 July 2014 (UTC)

New report on national security threat of global warming

The New York Times reported May 13, 2014 on a new report from the Center for Naval Analyses, Military Advisory Board on the threat to national security due to global warming. Perhaps this should be included in this article. The NYT story includes a quote from John Conger, the Pentagon's deputy under secretary of defense for installations and environment, "The department certainly agrees that climate change is having an impact on national security, whether by increasing global instability, by opening the Arctic or by increasing sea level and storm surge near our coastal installations." It also includes some lay analysis of the report, "found that climate change-induced drought in the Middle East and Africa is leading to conflicts over food and water and escalating longstanding regional and ethnic tensions into violent clashes." Of note is the use of the word is not may or will.

• Davenport, Coral (13 May 2014). "Climate change deemed growing security threat by military researchers". The New York Times.
• CNA Military Advisory Board (May 2014), National security and the accelerating risks of climate change (PDF), Alexandria, VA: Center for Naval Analyses (CNA).

MrBill3 (talk) 06:36, 14 May 2014 (UTC)

Nice contribution, MrBill the 3rd. 99.181.128.163 (talk) 04:12, 28 May 2014 (UTC)

Broken link

the citation with nubmer 1 links to nonexistent page. The link should be replaced with this one: http://www.aaas.org/sites/default/files/content_files/1021climate_letter.pdf Schokomann (talk) 22:14, 9 June 2014 (UTC)

Thanks;  Done NewsAndEventsGuy (talk) 00:06, 10 June 2014 (UTC)

Costs of delayed action aka GW effect on a species' ability to do a thing

Continued from previous thread - Talk:Effects of global warming#Scientific opinion on climate change impacts. Enescot (talk) 06:37, 26 July 2014 (UTC)

I don't think that this article should provide detailed information on the benefits and costs of reducing GHG emissions. The costs and benefits of climate change mitigation are already discussed here: climate change mitigation#Costs and benefits. Enescot (talk) 06:37, 26 July 2014 (UTC)

I agree that should not happen in detail, but that's what Template:Main is for. If we Venn Diagram these articles' topics there is bit of overlap in at least one (maybe more than one) respect. Do you agree that the following is true?

One effect of global warming is (for any number of examples) that it is changing the ability of the ____________ species to do _____________________

If that statement is true, then insert "human" and "intentionally control net forcing". That's a change happening to a component of the climate system. We should report that bit of earth/biological science just like we would any other.

We start to hint in this direction a little bit at Effects_of_global_warming#Abrupt_or_irreversible_changes but unless I missed it we don't explicitly discuss our own species potential for climate management as a matter of earth/biological science. Note this is a narrowing of my earlier position, where I think I was advocating this subject using the language of monetary finances. But money really isn't the point here. Earth/Biological science is. Our species potential ability to do a thing is being changed by global warming. NewsAndEventsGuy (talk) 12:02, 26 July 2014 (UTC)

Thanks for the clarification NewsAndEventsGuy (talk · contribs), but I'm not entirely clear on what you have in mind. In my view, the best division of content between this article and climate change mitigation is as follows:

Effects of global warming:

- Explains how climate change impacts vary with different magnitudes of global warming.

- Summarizes global warming projections, including both emissions reductions (mitigation) scenarios and non-mitigation scenarios. I should note that effects of global warming#Temperature changes is out-of-date. The low emissions SRES projections are generally lower than that of more recent non-mitigation scenarios.

- Refers the reader on to other articles that deal with policy responses to global warming (as I suggested previously).

Climate change mitigation:

- Explains the costs, benefits and risks of mitigation policies (monetized and non-monetized).

- Explains how there are different views over what policies are appropriate, e.g., in relation to acceptable risks from climate change impacts.

Enescot (talk) 06:59, 2 August 2014 (UTC)

Revise lead

I've been thinking of revising the lead section of the article. In my opinion, several changes should be made:
1. Revise information on observed and projected impacts. I don't think that enough information is given on how impacts vary with temperature. Any changes should avoid duplicating information that is already contained in the diagram which is used in the lead.
2. Revise diagram in lead. This should be updated based on the most recent Intergovernmental Panel on Climate Change report.
3. Add information on global warming projections. Many impacts increase with higher magnitudes of global warming. The lead should briefly mention how temperatures might change in the future, according to different scenarios.

Enescot (talk) 06:17, 2 August 2014 (UTC)

I've prepared a draft of the lead for discussion with other editors:

Summary of climate change impacts (SVG version).

Projected global warming in 2100 for a range of emission scenarios.

The effects of global warming are the environmental and social changes caused (directly or indirectly) by human emissions of greenhouse gases. There is a scientific consensus that climate change is occurring, and that human activities are the primary driver. Many impacts of climate change have already been observed, including glacier retreat, changes in the timing of seasonal events (e.g., earlier flowering of plants), and changes in agricultural productivity.

Future effects of climate change will vary depending on policy measures and social development. The two main policies to address climate change are reducing human greenhouse gas emissions (climate change mitigation) and adapting to the eventual impacts of climate change. Geoengineering is another policy option.

Near-term mitigation policies could significantly affect long-term climate change impacts. Aggressive mitigation policies might be able to limit global warming (in 2100) to around 2 °C or below, relative to pre-industrial levels. Without mitigation, increased energy demand and extensive use of fossil fuels might lead to global warming of around 4 °C. Higher magnitudes of global warming would be more difficult to adapt to, and would increase the risk of severe impacts.

References

Working Group II and III's contributions (WG2 and WG3) to the Intergovernmental Panel on Climate Change 5th Assessment Report. WG2: [12] (archive url): Summary for Policymakers; Technical Summary; Chapter 19. WG3: Summary for Policymakers.

Enescot (talk) 06:32, 7 October 2014 (UTC)