{"id":257741,"date":"2023-05-16T19:48:49","date_gmt":"2023-05-16T17:48:49","guid":{"rendered":"https:\/\/climatescience.press\/?p=257741"},"modified":"2023-05-16T19:48:52","modified_gmt":"2023-05-16T17:48:52","slug":"californias-mean-annual-temps-were-up-to-3-8c-warmer-than-today-during-the-last-glacial","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=257741","title":{"rendered":"California\u2019s Mean Annual Temps Were Up To 3.8\u00b0C Warmer Than Today During The Last Glacial"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

From NoTricksZone<\/a><\/p>\n\n\n\n

By\u00a0Kenneth Richard<\/a>\u00a0on\u00a0<\/em>15. May 2023<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

From 14,000 to 45,000 years ago, when the atmospheric CO2 values were said to be under 200 ppm, California lakes record millennial-scale mean annual air temperature (MAAT) variations of over 12\u00b0C and intervals when it was nearly 4\u00b0C warmer than modern.<\/strong><\/p>\n\n\n\n

Per a new paleotemperature reconstruction (Olson et al., 2023<\/a><\/strong>) from a California lake, there were periods during the last glacial when MAATs were both significantly colder (11.8\u00b0C) and warmer (23.9\u00b0C) than today (20.1\u00b0C).<\/p>\n\n\n\n

The Holocene, ~250-275 ppm CO2, has also had periods when paleotemperatures were multiple degrees warmer than modern.<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n
Image Source:\u00a0Olson et al., 2023<\/a><\/strong><\/h6>\n\n\n\n

<\/p>\n\n\n\n

Another California paleotemperature reconstruction (Feakins et al., 2019<\/a><\/strong>) also indicates the last glacial had abrupt warm-up periods reaching 10-15\u00b0C and MAATs ranging up to 4 to 5\u00b0C warmer than today (18\u00b0C vs. 22-23\u00b0C) between 31,000 and 24,000 years ago.<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n
Image Source:\u00a0Feakins et al., 2019<\/a><\/strong><\/h6>\n\n\n\n

<\/p>\n\n\n\n

These temperature reconstructions do not support the contention that atmospheric CO2 concentrations are a driver of climate variations.<\/p>\n","protected":false},"excerpt":{"rendered":"

From 14,000 to 45,000 years ago, when the atmospheric CO2 values were said to be under 200 ppm, California lakes record millennial-scale mean annual air temperature (MAAT) variations of over 12\u00b0C and intervals when it was nearly 4\u00b0C warmer than modern.<\/p>\n","protected":false},"author":121246920,"featured_media":257747,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_coblocks_attr":"","_coblocks_dimensions":"","_coblocks_responsive_height":"","_coblocks_accordion_ie_support":"","_crdt_document":"","advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1],"tags":[691818076,691818192],"class_list":{"0":"post-257741","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","6":"hentry","7":"category-uncategorized","8":"tag-co2","9":"tag-holocene","11":"fallback-thumbnail"},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/05\/00rainforest.jpg?fit=1440%2C960&ssl=1","jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paxLW1-1537","jetpack-related-posts":[{"id":376823,"url":"https:\/\/climatescience.press\/?p=376823","url_meta":{"origin":257741,"position":0},"title":"\u00a0New Study: Central Africa Was At Least 2.5\u00b0C Warmer Than Today 7000 Years Ago","author":"uwe.roland.gross","date":"30\/04\/2025","format":false,"excerpt":"Yet another region of the globe has failed to cooperate with anthropogenic \u201cglobal\u201d warming narrative.","rel":"","context":"In \"brGDGT (branched glycerol dialkyl glycerol tetraether)\"","block_context":{"text":"brGDGT (branched glycerol dialkyl glycerol tetraether)","link":"https:\/\/climatescience.press\/?tag=brgdgt-branched-glycerol-dialkyl-glycerol-tetraether"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/04\/0Screenshot-2025-04-30-090123.png?fit=1200%2C687&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/04\/0Screenshot-2025-04-30-090123.png?fit=1200%2C687&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/04\/0Screenshot-2025-04-30-090123.png?fit=1200%2C687&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/04\/0Screenshot-2025-04-30-090123.png?fit=1200%2C687&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/04\/0Screenshot-2025-04-30-090123.png?fit=1200%2C687&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":333324,"url":"https:\/\/climatescience.press\/?p=333324","url_meta":{"origin":257741,"position":1},"title":"Central Italy Was 3-4\u00b0C Warmer Than Today About 10,000 to 12,000 Years Ago","author":"uwe.roland.gross","date":"20\/06\/2024","format":false,"excerpt":"In a new study, scientists use the new \u201costracod-clumped isotope thermometer\u201d to reconstruct a much warmer Late Pleistocene\/Early Holocene Mediterranean climate.","rel":"","context":"In \"220-230 ppm range\"","block_context":{"text":"220-230 ppm range","link":"https:\/\/climatescience.press\/?tag=220-230-ppm-range"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/037225813515_ba707da1a3_b.jpg?fit=1024%2C683&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/037225813515_ba707da1a3_b.jpg?fit=1024%2C683&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/037225813515_ba707da1a3_b.jpg?fit=1024%2C683&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/037225813515_ba707da1a3_b.jpg?fit=1024%2C683&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":337388,"url":"https:\/\/climatescience.press\/?p=337388","url_meta":{"origin":257741,"position":2},"title":"New Study: Central Europe Was \u20182-5\u00b0C Warmer Than Present\u2019 Throughout Most Of The Holocene","author":"uwe.roland.gross","date":"24\/07\/2024","format":false,"excerpt":"There were millennia during the past glacial (when CO2 levels were under 200 ppm) that were as warm or warmer than today.","rel":"","context":"In \"Central Europe\"","block_context":{"text":"Central Europe","link":"https:\/\/climatescience.press\/?tag=central-europe"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0hesseflatow-clark-filio-neolithic-village-after-zden-k-2022.jpg?fit=1200%2C924&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0hesseflatow-clark-filio-neolithic-village-after-zden-k-2022.jpg?fit=1200%2C924&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0hesseflatow-clark-filio-neolithic-village-after-zden-k-2022.jpg?fit=1200%2C924&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0hesseflatow-clark-filio-neolithic-village-after-zden-k-2022.jpg?fit=1200%2C924&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0hesseflatow-clark-filio-neolithic-village-after-zden-k-2022.jpg?fit=1200%2C924&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":335660,"url":"https:\/\/climatescience.press\/?p=335660","url_meta":{"origin":257741,"position":3},"title":"An Giant Oyster Shell Discovery Suggests Early Holocene Seas Were 4\u00b0C (Up To 8\u00b0C) Warmer Than Today","author":"uwe.roland.gross","date":"06\/07\/2024","format":false,"excerpt":"Scientists continue to uncover evidence of a much warmer Early Holocene, when CO2 hovered near 260 ppm.","rel":"","context":"In \"Climate change\"","block_context":{"text":"Climate change","link":"https:\/\/climatescience.press\/?tag=climate-change"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/07473483208_0af764dcab_b.jpg?fit=1024%2C683&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/07473483208_0af764dcab_b.jpg?fit=1024%2C683&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/07473483208_0af764dcab_b.jpg?fit=1024%2C683&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/07473483208_0af764dcab_b.jpg?fit=1024%2C683&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":387689,"url":"https:\/\/climatescience.press\/?p=387689","url_meta":{"origin":257741,"position":4},"title":"New Study: The Arctic Was 9\u00b0C Warmer Than Today During The Holocene Thermal Maximum","author":"uwe.roland.gross","date":"09\/07\/2025","format":false,"excerpt":"Holocene (11,700 to 8,200 years ago) Arctic (Svalbard) temperatures \u201cwere up to 9\u00b0C higher than today\u201d according to the authors of a\u00a0new\u00a0Nature\u00a0journal study. At that time CO2 was thought to only hover around 260 ppm.","rel":"","context":"In \"Arctic\"","block_context":{"text":"Arctic","link":"https:\/\/climatescience.press\/?tag=arctic"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/07\/0AQMcRLd2Kk4Jh0iE7fNP3obsf-5tR9k5fVcJANmyS0v_l4UsMkrpljtXMMH9QGQ0XC4lEYVH02dSASIRTspYwZ2GFSRYa5qkzCW-Dy1IGaLxPsjL7NzdZrdXecJCsKk-N6Z10LH-LnRaS7w7jxDwRJM70cvYJA-1.jpeg?fit=1200%2C1200&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/07\/0AQMcRLd2Kk4Jh0iE7fNP3obsf-5tR9k5fVcJANmyS0v_l4UsMkrpljtXMMH9QGQ0XC4lEYVH02dSASIRTspYwZ2GFSRYa5qkzCW-Dy1IGaLxPsjL7NzdZrdXecJCsKk-N6Z10LH-LnRaS7w7jxDwRJM70cvYJA-1.jpeg?fit=1200%2C1200&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/07\/0AQMcRLd2Kk4Jh0iE7fNP3obsf-5tR9k5fVcJANmyS0v_l4UsMkrpljtXMMH9QGQ0XC4lEYVH02dSASIRTspYwZ2GFSRYa5qkzCW-Dy1IGaLxPsjL7NzdZrdXecJCsKk-N6Z10LH-LnRaS7w7jxDwRJM70cvYJA-1.jpeg?fit=1200%2C1200&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/07\/0AQMcRLd2Kk4Jh0iE7fNP3obsf-5tR9k5fVcJANmyS0v_l4UsMkrpljtXMMH9QGQ0XC4lEYVH02dSASIRTspYwZ2GFSRYa5qkzCW-Dy1IGaLxPsjL7NzdZrdXecJCsKk-N6Z10LH-LnRaS7w7jxDwRJM70cvYJA-1.jpeg?fit=1200%2C1200&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/07\/0AQMcRLd2Kk4Jh0iE7fNP3obsf-5tR9k5fVcJANmyS0v_l4UsMkrpljtXMMH9QGQ0XC4lEYVH02dSASIRTspYwZ2GFSRYa5qkzCW-Dy1IGaLxPsjL7NzdZrdXecJCsKk-N6Z10LH-LnRaS7w7jxDwRJM70cvYJA-1.jpeg?fit=1200%2C1200&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":338077,"url":"https:\/\/climatescience.press\/?p=338077","url_meta":{"origin":257741,"position":5},"title":"Climate Scientists Dishonestly Cherry-pick Wildfires to Push a Climate Crisis!","author":"uwe.roland.gross","date":"31\/07\/2024","format":false,"excerpt":"Egregious cherry-picking by alarmist climate scientists attempts to delude the public into believing that a slight increase in wildfire burnt acres can be blamed on rising CO2. First, they dishonestly ignore the scientific evidence that far more fires happened before the 1930s when CO2 and global temperatures were much lower\u2026","rel":"","context":"In \"Climate change\"","block_context":{"text":"Climate change","link":"https:\/\/climatescience.press\/?tag=climate-change"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0ad_213954899.webp?fit=1200%2C800&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0ad_213954899.webp?fit=1200%2C800&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0ad_213954899.webp?fit=1200%2C800&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0ad_213954899.webp?fit=1200%2C800&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/07\/0ad_213954899.webp?fit=1200%2C800&ssl=1&resize=1050%2C600 3x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/257741","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/users\/121246920"}],"replies":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=257741"}],"version-history":[{"count":4,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/257741\/revisions"}],"predecessor-version":[{"id":257749,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/257741\/revisions\/257749"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/media\/257747"}],"wp:attachment":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=257741"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=257741"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=257741"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}