{"id":707,"date":"2021-09-16T19:30:32","date_gmt":"2021-09-16T19:30:32","guid":{"rendered":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/chapter\/chapter-19-climate-change-physical-geology-2nd-edition\/"},"modified":"2021-09-16T19:43:18","modified_gmt":"2021-09-16T19:43:18","slug":"chapter-19-climate-change-physical-geology-2nd-edition","status":"publish","type":"chapter","link":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/chapter\/chapter-19-climate-change-physical-geology-2nd-edition\/","title":{"raw":"Chapter 19 Climate Change -- Physical Geology &#8211; 2nd Edition","rendered":"Chapter 19 Climate Change &#8212; Physical Geology &#8211; 2nd Edition"},"content":{"raw":"\n\n<div class=\"part\" id=\"chapter-19-climate-change\"><div class=\"part-title-wrap\"><h3 class=\"part-number\"><\/h3><h1 class=\"part-title\">Chapter 19 Climate Change<\/h1><\/div><div><div>\n  &lt;!-- pb_fixme --&gt;\n  <div class=\"textbox textbox--learning-objectives\">\n    <div class=\"textbox__header\">\n      <p>After reading this chapter, completing the exercises within it, and answering the questions at the end, you should be able to:<\/p>\n      <ul>\n        <li>Summarize the properties of greenhouse gases and their role in controlling the climate.<\/li>\n        <li>Explain the difference between climate forcing and climate feedbacks.<\/li>\n        <li>Describe the mechanisms of climate forcing related to solar evolution, continental drift, continental collisions, volcanism, Earth and Sun orbital variations, and changing ocean currents.<\/li>\n        <li>Describe the significance of albedo to climate and how the melting of ice or snow and deforestation affect albedo.<\/li>\n        <li>Explain the roles of the melting of permafrost, breakdown of methane hydrates, and temperature-related solubility of CO<sub>2<\/sub> as positive feedbacks.<\/li>\n        <li>Describe some of the ways that our extraction and use of fossil fuels contribute to climate change.<\/li>\n        <li>Explain how food production contributes to climate change.<\/li>\n        <li>List some of the steps that we can take as individuals to limit our personal contribution to climate change.<\/li>\n        <li>Describe the role of climate change in sea-level rise, and why we are already committed to more than a metre of additional sea-level rise.<\/li>\n        <li>Explain the link between climate change and the distribution of diseases and pests.<\/li>\n      <\/ul>\n    <\/div>\n  <\/div>\n  <p>&nbsp;<\/p>\n  <div class=\"wp-caption aligncenter\" id=\"attachment_692\" style=\"width: 900px\">\n    <img src=\"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-content\/uploads\/sites\/15\/2021\/09\/Core-from-Ocean-Drilling-Program-hole-1024x414-1.png\" alt=\"\" class=\"wp-image-692\" width=\"900\" height=\"364\">\n    <div class=\"wp-caption-text\" id=\"caption-attachment-692\">Figure 19.0.1 Core from Ocean Drilling Program hole 1220b (southeast of Hawaii) showing the boundary between the Paleocene and the Eocene (at 55.8 Ma). Marine life was decimated during the 100,000 years of the Paleocene-Eocene thermal maximum, and the dark part of the core represents the absence of carbonate sediment from planktonic organisms. The scale is in centimetres.<\/div>\n  <\/div>\n  <p>If one thing has been constant about Earth\u2019s climate over geological time, it is its constant change. In the geological record, we can see this in the evidence of glaciations in the distant past (see section 16.1 in Chapter 16), and we can also detect periods of extreme warmth by looking at the isotope composition of sea-floor sediments, such as those in the core shown in Figure 19.0.1. Not only has the climate changed frequently, the temperature fluctuations have been very significant. Today\u2019s mean global temperature is about 15\u00b0C. During Snowball Earth times, the global mean was as cold as \u221250\u00b0C, while at various times during the Paleozoic and Mesozoic and during the Paleocene-Eocene thermal maximum, it was close to +30\u00b0C.<\/p>\n  <p>But in spite of these dramatic climate changes, Earth has been habitable from very early in its history\u2014as soon as liquid water was present\u2014right through to the present day. That continuous habitability is perhaps a little more surprising than you might think, as we\u2019ll see below.<\/p>\n  <p>A significant part of this chapter is about the natural processes of climate change and how they work. It\u2019s critically important to be aware of those natural climate change processes if we want to understand anthropogenic climate change. First, this awareness helps us to understand why our activities are causing the present-day climate to change, and second, it allows us to distinguish between natural and anthropogenic processes in the climate record of the past 250 years.<\/p>\n  <h3>Media Attributions<\/h3>\n  <ul>\n    <li>Figure 19.0.1: \u201c<a href=\"http:\/\/www-odp.tamu.edu\/publications\/199_IR\/chap_13\/c13_f4.htm\">199-1220B-20X-2<\/a>\u201c \u00a9 Ocean Drilling Program. Adapted by Steven Earle. Used with permission.<\/li>\n  <\/ul>\n  &lt;!-- pb_fixme --&gt;\n<\/div>\n<\/div><\/div>\n","rendered":"<div class=\"part\" id=\"chapter-19-climate-change\">\n<div class=\"part-title-wrap\">\n<h3 class=\"part-number\"><\/h3>\n<h1 class=\"part-title\">Chapter 19 Climate Change<\/h1>\n<\/div>\n<div>\n<div>\n  &lt;!&#8211; pb_fixme &#8211;&gt;<\/p>\n<div class=\"textbox textbox--learning-objectives\">\n<div class=\"textbox__header\">\n<p>After reading this chapter, completing the exercises within it, and answering the questions at the end, you should be able to:<\/p>\n<ul>\n<li>Summarize the properties of greenhouse gases and their role in controlling the climate.<\/li>\n<li>Explain the difference between climate forcing and climate feedbacks.<\/li>\n<li>Describe the mechanisms of climate forcing related to solar evolution, continental drift, continental collisions, volcanism, Earth and Sun orbital variations, and changing ocean currents.<\/li>\n<li>Describe the significance of albedo to climate and how the melting of ice or snow and deforestation affect albedo.<\/li>\n<li>Explain the roles of the melting of permafrost, breakdown of methane hydrates, and temperature-related solubility of CO<sub>2<\/sub> as positive feedbacks.<\/li>\n<li>Describe some of the ways that our extraction and use of fossil fuels contribute to climate change.<\/li>\n<li>Explain how food production contributes to climate change.<\/li>\n<li>List some of the steps that we can take as individuals to limit our personal contribution to climate change.<\/li>\n<li>Describe the role of climate change in sea-level rise, and why we are already committed to more than a metre of additional sea-level rise.<\/li>\n<li>Explain the link between climate change and the distribution of diseases and pests.<\/li>\n<\/ul><\/div>\n<\/p><\/div>\n<p>&nbsp;<\/p>\n<div class=\"wp-caption aligncenter\" id=\"attachment_692\" style=\"width: 900px\">\n    <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-content\/uploads\/sites\/15\/2021\/09\/Core-from-Ocean-Drilling-Program-hole-1024x414-1.png\" alt=\"\" class=\"wp-image-692\" width=\"900\" height=\"364\" \/><\/p>\n<div class=\"wp-caption-text\" id=\"caption-attachment-692\">Figure 19.0.1 Core from Ocean Drilling Program hole 1220b (southeast of Hawaii) showing the boundary between the Paleocene and the Eocene (at 55.8 Ma). Marine life was decimated during the 100,000 years of the Paleocene-Eocene thermal maximum, and the dark part of the core represents the absence of carbonate sediment from planktonic organisms. The scale is in centimetres.<\/div>\n<\/p><\/div>\n<p>If one thing has been constant about Earth\u2019s climate over geological time, it is its constant change. In the geological record, we can see this in the evidence of glaciations in the distant past (see section 16.1 in Chapter 16), and we can also detect periods of extreme warmth by looking at the isotope composition of sea-floor sediments, such as those in the core shown in Figure 19.0.1. Not only has the climate changed frequently, the temperature fluctuations have been very significant. Today\u2019s mean global temperature is about 15\u00b0C. During Snowball Earth times, the global mean was as cold as \u221250\u00b0C, while at various times during the Paleozoic and Mesozoic and during the Paleocene-Eocene thermal maximum, it was close to +30\u00b0C.<\/p>\n<p>But in spite of these dramatic climate changes, Earth has been habitable from very early in its history\u2014as soon as liquid water was present\u2014right through to the present day. That continuous habitability is perhaps a little more surprising than you might think, as we\u2019ll see below.<\/p>\n<p>A significant part of this chapter is about the natural processes of climate change and how they work. It\u2019s critically important to be aware of those natural climate change processes if we want to understand anthropogenic climate change. First, this awareness helps us to understand why our activities are causing the present-day climate to change, and second, it allows us to distinguish between natural and anthropogenic processes in the climate record of the past 250 years.<\/p>\n<h3>Media Attributions<\/h3>\n<ul>\n<li>Figure 19.0.1: \u201c<a href=\"http:\/\/www-odp.tamu.edu\/publications\/199_IR\/chap_13\/c13_f4.htm\">199-1220B-20X-2<\/a>\u201c \u00a9 Ocean Drilling Program. Adapted by Steven Earle. Used with permission.<\/li>\n<\/ul>\n<p>  &lt;!&#8211; pb_fixme &#8211;&gt;\n<\/p><\/div>\n<\/div>\n<\/div>\n","protected":false},"author":8,"menu_order":135,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-707","chapter","type-chapter","status-publish","hentry"],"part":3,"_links":{"self":[{"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/chapters\/707","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/wp\/v2\/users\/8"}],"version-history":[{"count":1,"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/chapters\/707\/revisions"}],"predecessor-version":[{"id":1038,"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/chapters\/707\/revisions\/1038"}],"part":[{"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/chapters\/707\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/wp\/v2\/media?parent=707"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/pressbooks\/v2\/chapter-type?post=707"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/wp\/v2\/contributor?post=707"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.ccconline.org\/physicalgeology\/wp-json\/wp\/v2\/license?post=707"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}