www.carbonbrief.org Open in urlscan Pro
2606:4700:3030::6815:341a  Public Scan

Form analysis
3 forms found in the DOM

POST https://www.carbonbrief.org/search

<form data-sf-form-id="41554" data-is-rtl="0" data-maintain-state="" data-results-url="https://www.carbonbrief.org/search" data-ajax-form-url="https://www.carbonbrief.org/?sfid=41554&amp;sf_action=get_data&amp;sf_data=form"
  data-display-result-method="shortcode" data-use-history-api="1" data-template-loaded="0" data-lang-code="en" data-ajax="0" data-init-paged="1" data-auto-update="" action="https://www.carbonbrief.org/search" method="post" class="searchandfilter"
  id="search-filter-form-41554" autocomplete="off" data-instance-count="1">
  <ul>
    <li class="sf-field-search" data-sf-field-name="search" data-sf-field-type="search" data-sf-field-input-type=""> <label><input placeholder="Search …" name="_sf_search[]" class="sf-input-text" type="text" value="" title=""></label> </li>
    <li class="sf-field-post_type" data-sf-field-name="_sf_post_type" data-sf-field-type="post_type" data-sf-field-input-type="select">
      <h4>Type</h4> <label>
        <select name="_sf_post_type[]" class="sf-input-select" title="">
          <option class="sf-level-0 sf-item-0 sf-option-active" selected="selected" data-sf-depth="0" value="">All Types</option>
          <option class="sf-level-0 " data-sf-depth="0" value="post">Articles</option>
          <option class="sf-level-0 " data-sf-depth="0" value="dailybrief">Daily Brief</option>
        </select>
      </label>
    </li>
    <li class="sf-field-category" data-sf-field-name="_sft_category" data-sf-field-type="category" data-sf-field-input-type="select">
      <h4>Topic</h4> <label>
        <select name="_sft_category[]" class="sf-input-select" title="">
          <option class="sf-level-0 sf-item-0 sf-option-active" selected="selected" data-sf-count="0" data-sf-depth="0" value="">All Items</option>
          <option class="sf-level-0 sf-item-2022" data-sf-count="58" data-sf-depth="0" value="1-5c">1.5C</option>
          <option class="sf-level-0 sf-item-35" data-sf-count="71" data-sf-depth="0" value="antarctic">Antarctic</option>
          <option class="sf-level-0 sf-item-34" data-sf-count="102" data-sf-depth="0" value="arctic">Arctic</option>
          <option class="sf-level-0 sf-item-43" data-sf-count="59" data-sf-depth="0" value="attribution">Attribution</option>
          <option class="sf-level-0 sf-item-2058" data-sf-count="14" data-sf-depth="0" value="carbon-budgets">Carbon budgets</option>
          <option class="sf-level-0 sf-item-2214" data-sf-count="127" data-sf-depth="0" value="china-policy">China Policy</option>
          <option class="sf-level-0 sf-item-1973" data-sf-count="54" data-sf-depth="0" value="climate-modelling">Climate modelling</option>
          <option class="sf-level-0 sf-item-27" data-sf-count="44" data-sf-depth="0" value="climate-sensitivity">Climate sensitivity</option>
          <option class="sf-level-0 sf-item-54" data-sf-count="171" data-sf-depth="0" value="coal">Coal</option>
          <option class="sf-level-0 sf-item-62" data-sf-count="80" data-sf-depth="0" value="paris-2015">COP21 Paris</option>
          <option class="sf-level-0 sf-item-1638" data-sf-count="17" data-sf-depth="0" value="cop22-marrakech">COP22 Marrakech</option>
          <option class="sf-level-0 sf-item-1948" data-sf-count="7" data-sf-depth="0" value="cop23-bonn">COP23 Bonn</option>
          <option class="sf-level-0 sf-item-2118" data-sf-count="6" data-sf-depth="0" value="cop24-katowice">COP24 Katowice</option>
          <option class="sf-level-0 sf-item-2155" data-sf-count="4" data-sf-depth="0" value="cop25">COP25 Madrid</option>
          <option class="sf-level-0 sf-item-2520" data-sf-count="11" data-sf-depth="0" value="glasgow-2021">COP26 Glasgow</option>
          <option class="sf-level-0 sf-item-2802" data-sf-count="4" data-sf-depth="0" value="cop27-sharm-el-sheikh">COP27 Sharm el-Sheikh</option>
          <option class="sf-level-0 sf-item-2057" data-sf-count="19" data-sf-depth="0" value="country-profiles">Country profiles</option>
          <option class="sf-level-0 sf-item-42" data-sf-count="54" data-sf-depth="0" value="drought">Drought</option>
          <option class="sf-level-0 sf-item-38" data-sf-count="28" data-sf-depth="0" value="el-nino">El Niño</option>
          <option class="sf-level-0 sf-item-52" data-sf-count="358" data-sf-depth="0" value="emissions">Emissions</option>
          <option class="sf-level-0 sf-item-2" data-sf-count="668" data-sf-depth="0" value="energy">Energy</option>
          <option class="sf-level-0 sf-item-60" data-sf-count="44" data-sf-depth="0" value="eu-emissions">EU emissions</option>
          <option class="sf-level-0 sf-item-65" data-sf-count="110" data-sf-depth="0" value="eu-policy">EU policy</option>
          <option class="sf-level-0 sf-item-68" data-sf-count="102" data-sf-depth="0" value="explainers">Explainers</option>
          <option class="sf-level-0 sf-item-19" data-sf-count="241" data-sf-depth="0" value="extreme-weather">Extreme weather</option>
          <option class="sf-level-0 sf-item-69" data-sf-count="58" data-sf-depth="0" value="factchecks">Factchecks</option>
          <option class="sf-level-0 sf-item-75" data-sf-count="84" data-sf-depth="0" value="features">Features</option>
          <option class="sf-level-0 sf-item-41" data-sf-count="86" data-sf-depth="0" value="floods">Floods</option>
          <option class="sf-level-0 sf-item-46" data-sf-count="95" data-sf-depth="0" value="food-farming">Food and farming</option>
          <option class="sf-level-0 sf-item-28" data-sf-count="42" data-sf-depth="0" value="geoengineering">Geoengineering</option>
          <option class="sf-level-0 sf-item-26" data-sf-count="81" data-sf-depth="0" value="ghgs-aerosols">GHGs and aerosols</option>
          <option class="sf-level-0 sf-item-37" data-sf-count="40" data-sf-depth="0" value="glaciers">Glaciers</option>
          <option class="sf-level-0 sf-item-58" data-sf-count="127" data-sf-depth="0" value="global-emissions">Global emissions</option>
          <option class="sf-level-0 sf-item-23" data-sf-count="186" data-sf-depth="0" value="global-temperature">Global temperature</option>
          <option class="sf-level-0 sf-item-72" data-sf-count="301" data-sf-depth="0" value="guest-posts">Guest posts</option>
          <option class="sf-level-0 sf-item-39" data-sf-count="75" data-sf-depth="0" value="heatwaves">Heatwaves</option>
          <option class="sf-level-0 sf-item-29" data-sf-count="25" data-sf-depth="0" value="hiatus">Hiatus</option>
          <option class="sf-level-0 sf-item-48" data-sf-count="83" data-sf-depth="0" value="human-security">Human security</option>
          <option class="sf-level-0 sf-item-18" data-sf-count="162" data-sf-depth="0" value="ice">Ice</option>
          <option class="sf-level-0 sf-item-4" data-sf-count="795" data-sf-depth="0" value="in-focus">In Focus</option>
          <option class="sf-level-0 sf-item-71" data-sf-count="110" data-sf-depth="0" value="infographics">Infographics</option>
          <option class="sf-level-0 sf-item-63" data-sf-count="157" data-sf-depth="0" value="international-policy">International policy</option>
          <option class="sf-level-0 sf-item-70" data-sf-count="100" data-sf-depth="0" value="interviews">Interviews</option>
          <option class="sf-level-0 sf-item-22" data-sf-count="126" data-sf-depth="0" value="ipcc">IPCC</option>
          <option class="sf-level-0 sf-item-32" data-sf-count="55" data-sf-depth="0" value="marine-life">Marine life</option>
          <option class="sf-level-0 sf-item-74" data-sf-count="106" data-sf-depth="0" value="media-analysis">Media analysis</option>
          <option class="sf-level-0 sf-item-20" data-sf-count="228" data-sf-depth="0" value="nature">Nature</option>
          <option class="sf-level-0 sf-item-2078" data-sf-count="34" data-sf-depth="0" value="negative-emissions">Negative emissions</option>
          <option class="sf-level-0 sf-item-56" data-sf-count="73" data-sf-depth="0" value="nuclear">Nuclear</option>
          <option class="sf-level-0 sf-item-33" data-sf-count="25" data-sf-depth="0" value="ocean-acidification">Ocean acidification</option>
          <option class="sf-level-0 sf-item-31" data-sf-count="65" data-sf-depth="0" value="ocean-warming">Ocean warming</option>
          <option class="sf-level-0 sf-item-17" data-sf-count="139" data-sf-depth="0" value="oceans">Oceans</option>
          <option class="sf-level-0 sf-item-55" data-sf-count="185" data-sf-depth="0" value="oil-and-gas">Oil and gas</option>
          <option class="sf-level-0 sf-item-21" data-sf-count="261" data-sf-depth="0" value="people">People</option>
          <option class="sf-level-0 sf-item-44" data-sf-count="105" data-sf-depth="0" value="plants-forests">Plants and forests</option>
          <option class="sf-level-0 sf-item-3" data-sf-count="718" data-sf-depth="0" value="policy">Policy</option>
          <option class="sf-level-0 sf-item-47" data-sf-count="68" data-sf-depth="0" value="public-health">Public health</option>
          <option class="sf-level-0 sf-item-50" data-sf-count="53" data-sf-depth="0" value="public-opinion">Public opinion</option>
          <option class="sf-level-0 sf-item-53" data-sf-count="219" data-sf-depth="0" value="renewables">Renewables</option>
          <option class="sf-level-0 sf-item-61" data-sf-count="104" data-sf-depth="0" value="rest-of-world-emissions">Rest of world emissions</option>
          <option class="sf-level-0 sf-item-66" data-sf-count="110" data-sf-depth="0" value="rest-of-world-policy">Rest of world policy</option>
          <option class="sf-level-0 sf-item-25" data-sf-count="22" data-sf-depth="0" value="rest-of-world-temperature">Rest of world temperature</option>
          <option class="sf-level-0 sf-item-49" data-sf-count="92" data-sf-depth="0" value="risk-adaptation">Risk and adaptation</option>
          <option class="sf-level-0 sf-item-1" data-sf-count="2146" data-sf-depth="0" value="science">Science</option>
          <option class="sf-level-0 sf-item-51" data-sf-count="50" data-sf-depth="0" value="science-communication">Science communication</option>
          <option class="sf-level-0 sf-item-36" data-sf-count="82" data-sf-depth="0" value="sea-ice">Sea ice</option>
          <option class="sf-level-0 sf-item-30" data-sf-count="53" data-sf-depth="0" value="sea-level-rise">Sea level rise</option>
          <option class="sf-level-0 sf-item-2063" data-sf-count="22" data-sf-depth="0" value="state-of-the-climate">State of the climate</option>
          <option class="sf-level-0 sf-item-40" data-sf-count="59" data-sf-depth="0" value="storms">Storms</option>
          <option class="sf-level-0 sf-item-57" data-sf-count="134" data-sf-depth="0" value="technology">Technology</option>
          <option class="sf-level-0 sf-item-16" data-sf-count="311" data-sf-depth="0" value="temperature">Temperature</option>
          <option class="sf-level-0 sf-item-2161" data-sf-count="11" data-sf-depth="0" value="tipping-points">Tipping points</option>
          <option class="sf-level-0 sf-item-1897" data-sf-count="24" data-sf-depth="0" value="translations">Translations</option>
          <option class="sf-level-0 sf-item-59" data-sf-count="105" data-sf-depth="0" value="uk-emissions">UK emissions</option>
          <option class="sf-level-0 sf-item-64" data-sf-count="304" data-sf-depth="0" value="uk-policy">UK policy</option>
          <option class="sf-level-0 sf-item-24" data-sf-count="33" data-sf-depth="0" value="uk-temperature">UK temperature</option>
          <option class="sf-level-0 sf-item-2041" data-sf-count="43" data-sf-depth="0" value="un-climate-talks">UN climate talks</option>
          <option class="sf-level-0 sf-item-1835" data-sf-count="28" data-sf-depth="0" value="us-policy">US Policy</option>
          <option class="sf-level-0 sf-item-2177" data-sf-count="4" data-sf-depth="0" value="webinars">Webinars</option>
          <option class="sf-level-0 sf-item-2071" data-sf-count="16" data-sf-depth="0" value="wildfires">Wildfires</option>
          <option class="sf-level-0 sf-item-45" data-sf-count="86" data-sf-depth="0" value="wildlife">Wildlife</option>
        </select>
      </label>
    </li>
    <li class="sf-field-post_date" data-sf-field-name="_sf_post_date" data-sf-field-type="post_date" data-sf-field-input-type="daterange">
      <h4>Date Range</h4>
      <ul class="sf_date_field" data-date-format="dd/mm/yy" data-date-use-year-dropdown="0" data-date-use-month-dropdown="0">
        <li> <span class="sf-date-prefix">From:</span><label><input class="sf-datepicker sf-input-date sf-input-text hasDatepicker" name="_sf_post_date[]" type="text" value="" title="" id="dp1670974975209"></label> </li>
        <li> <span class="sf-date-prefix">To:</span><label><input class="sf-datepicker sf-input-date sf-input-text hasDatepicker" name="_sf_post_date[]" type="text" value="" title="" id="dp1670974975210"></label> </li>
      </ul>
    </li>
    <li class="sf-field-sort_order" data-sf-field-name="_sf_sort_order" data-sf-field-type="sort_order" data-sf-field-input-type="select">
      <h4>Sort</h4> <label>
        <select name="_sf_sort_order[]" class="sf-input-select" title="">
          <option class="sf-level-0 sf-item-0 sf-option-active" selected="selected" data-sf-depth="0" value="">Sort Results By</option>
          <option class="sf-level-0 " data-sf-depth="0" value="date+desc">Title (Deecending)</option>
          <option class="sf-level-0 " data-sf-depth="0" value="date+asc">Title (Ascending)</option>
        </select>
      </label>
    </li>
    <li class="sf-field-submit" data-sf-field-name="submit" data-sf-field-type="submit" data-sf-field-input-type=""><input type="submit" name="_sf_submit" value="Submit"></li>
  </ul>
</form>

Name: revue-form — POST https://www.getrevue.co/profile/CarbonBriefDailyBriefing/add_subscriber

<form action="https://www.getrevue.co/profile/CarbonBriefDailyBriefing/add_subscriber" method="post" id="revueForm" name="revue-form" target="_blank" class="dailybrief-signup">
  <input class="revue-form-field" placeholder="Your email address..." type="email" name="member[email]" id="member_email">
  <div class="deDrop">
    <select name="type" class="brief-type" id="brief-type">
      <option data-action="https://www.getrevue.co/profile/CarbonBriefDailyBriefing/add_subscriber" value="daily" selected="selected">Daily Briefing</option>
      <option data-action="https://www.getrevue.co/profile/CarbonBriefWeeklyBriefing/add_subscriber" value="weekly">Weekly Briefing</option>
      <option data-action="https://www.getrevue.co/profile/ChinaWeekly" value="china">China</option>
      <option data-action="https://www.getrevue.co/profile/CarbonBriefCropped" value="cropped">Cropped</option>
    </select>
  </div>
  <input type="submit" value="Subscribe" name="member[subscribe]" id="member_submit" class="subscribe-button">
</form>

Name: revue-form — POST https://www.getrevue.co/profile/CarbonBriefDailyBriefing/add_subscriber

<form action="https://www.getrevue.co/profile/CarbonBriefDailyBriefing/add_subscriber" method="post" id="revueForm-block" name="revue-form" target="_blank" class="dailybrief-signup">
  <input class="revue-form-field email" placeholder="Your email address..." type="email" name="member[email]" id="member_email">
  <select name="type" class="brief-type select-brief" id="brief-type-block">
    <option data-action="https://www.getrevue.co/profile/CarbonBriefDailyBriefing/add_subscriber" value="daily" selected="selected">Daily Briefing</option>
    <option data-action="https://www.getrevue.co/profile/CarbonBriefWeeklyBriefing/add_subscriber" value="weekly">Weekly Briefing</option>
    <option data-action="https://www.getrevue.co/profile/ChinaWeekly" value="china">China</option>
    <option data-action="https://www.getrevue.co/profile/CarbonBriefCropped" value="cropped">Cropped</option>
  </select>
  <input type="submit" value="Subscribe" name="member[subscribe]" id="member_submit" class="subscribe-button">
</form>

Text Content

SECTIONS

 * Science
   * Climate modelling
   * Extreme weather
   * Ice
   * IPCC
   * Nature
   * Oceans
   * People
   * Temperature
 * Energy
   * Coal
   * Emissions
   * Nuclear
   * Oil and gas
   * Renewables
   * Technology
 * Policy
   * China Policy
   * EU policy
   * International policy
   * Rest of world policy
   * UK policy
   * UN climate talks
   * US Policy
 * In Focus
   * Country profiles
   * Explainers
   * Factchecks
   * Features
   * Guest posts
   * Infographics
   * Interviews
   * Media analysis
   * State of the climate
   * Translations
   * Webinars
 * Daily Brief

MENU

 * About Us
 * China
 * China Briefing
 * Comments Policy
 * Contact Us
 * Cookies Policy
 * Cropped
 * Daily Brief
 * Energy
   * Coal
   * Emissions
     * Global emissions
     * Rest of world emissions
     * UK emissions
   * EU emissions
   * Nuclear
   * Oil and gas
   * Renewables
   * Technology
 * Global South Climate Database
 * GSCD dummy
 * Home
 * In focus
   * Country profiles
   * Explainers
   * Factchecks
   * Features
   * Guest posts
   * Infographics
   * Interviews
   * Media analysis
   * State of the climate
   * Translations
   * Webinars
 * Newsletters
 * Policy
   * China Policy
   * EU policy
   * International policy
   * Rest of world policy
   * UK policy
   * UN climate talks
     * COP21 Paris
     * COP22 Marrakech
     * COP23 Bonn
     * COP24 Katowice
     * COP25 Madrid
     * COP26 Glasgow
     * COP27 Sharm el-Sheikh
   * US Policy
 * Privacy Policy
 * Science
   * Climate modelling
   * Extreme weather
     * Attribution
     * Drought
     * El Niño
     * Floods
     * Heatwaves
     * Storms
     * Wildfires
   * Geoengineering
   * Ice
     * Antarctic
     * Arctic
     * Glaciers
     * Sea ice
   * IPCC
   * Nature
     * Food and farming
     * Plants and forests
     * Wildlife
   * Oceans
     * Marine life
     * Ocean acidification
     * Ocean warming
     * Sea level rise
   * People
     * Human security
     * Public health
     * Public opinion
     * Risk and adaptation
     * Science communication
   * Temperature
     * 1.5C
     * Carbon budgets
     * Climate sensitivity
     * GHGs and aerosols
     * Global temperature
     * Hiatus
     * Negative emissions
     * Rest of world temperature
     * Tipping points
     * UK temperature
 * Search
 * Thank you for subscribing

SOCIAL CHANNELS

 * Facebook
 * Twitter
 * LinkedIn
 * Instagram
 * Youtube
 * Rss

SEARCH ARCHIVE

 * 

 * TYPE
   
   All Types Articles Daily Brief

 * TOPIC
   
   All Items 1.5C Antarctic Arctic Attribution Carbon budgets China Policy
   Climate modelling Climate sensitivity Coal COP21 Paris COP22 Marrakech COP23
   Bonn COP24 Katowice COP25 Madrid COP26 Glasgow COP27 Sharm el-Sheikh Country
   profiles Drought El Niño Emissions Energy EU emissions EU policy Explainers
   Extreme weather Factchecks Features Floods Food and farming Geoengineering
   GHGs and aerosols Glaciers Global emissions Global temperature Guest posts
   Heatwaves Hiatus Human security Ice In Focus Infographics International
   policy Interviews IPCC Marine life Media analysis Nature Negative emissions
   Nuclear Ocean acidification Ocean warming Oceans Oil and gas People Plants
   and forests Policy Public health Public opinion Renewables Rest of world
   emissions Rest of world policy Rest of world temperature Risk and adaptation
   Science Science communication Sea ice Sea level rise State of the climate
   Storms Technology Temperature Tipping points Translations UK emissions UK
   policy UK temperature UN climate talks US Policy Webinars Wildfires Wildlife

 * DATE RANGE
   
   * From:
   * To:

 * SORT
   
   Sort Results By Title (Deecending) Title (Ascending)
 * 

 * Science
   * Climate modelling
   * Extreme weather
     * Attribution
     * Drought
     * El Niño
     * Floods
     * Heatwaves
     * Storms
     * Wildfires
   * Ice
     * Antarctic
     * Arctic
     * Glaciers
     * Sea ice
   * IPCC
   * Nature
     * Food and farming
     * Plants and forests
     * Wildlife
   * Oceans
     * Marine life
     * Ocean acidification
     * Ocean warming
     * Sea level rise
   * People
     * Human security
     * Public health
     * Public opinion
     * Risk and adaptation
     * Science communication
   * Temperature
     * Hiatus
     * 1.5C
     * Carbon budgets
     * Climate sensitivity
     * Geoengineering
     * GHGs and aerosols
     * Global temperature
     * Negative emissions
     * Rest of world temperature
     * Tipping points
     * UK temperature
   * Global South Climate Database
 * Energy
   * Coal
   * Emissions
     * EU emissions
     * Global emissions
     * Rest of world emissions
     * UK emissions
   * Nuclear
   * Oil and gas
   * Renewables
   * Technology
 * Policy
   * China Policy
   * EU policy
   * International policy
   * Rest of world policy
   * UK policy
   * UN climate talks
     * COP21 Paris
     * COP22 Marrakech
     * COP23 Bonn
     * COP24 Katowice
     * COP25 Madrid
     * COP26 Glasgow
     * COP27 Sharm el-Sheikh
   * US Policy
 * In focus
   * Country profiles
   * Explainers
   * Factchecks
   * Features
   * Guest posts
   * Infographics
   * Interviews
   * Media analysis
   * Translations
   * Webinars
 * Daily Brief

Subscribe


Receive a Daily or Weekly summary of the most important articles direct to your
inbox, just enter your email below. By entering your email address you agree for
your data to be handled in accordance with our Privacy Policy.

Daily Briefing Weekly Briefing China Cropped
 * Science
   * Climate modelling
   * Extreme weather
     * Attribution
     * Drought
     * El Niño
     * Floods
     * Heatwaves
     * Storms
     * Wildfires
   * Ice
     * Antarctic
     * Arctic
     * Glaciers
     * Sea ice
   * IPCC
   * Nature
     * Food and farming
     * Plants and forests
     * Wildlife
   * Oceans
     * Marine life
     * Ocean acidification
     * Ocean warming
     * Sea level rise
   * People
     * Human security
     * Public health
     * Public opinion
     * Risk and adaptation
     * Science communication
   * Temperature
     * Hiatus
     * 1.5C
     * Carbon budgets
     * Climate sensitivity
     * Geoengineering
     * GHGs and aerosols
     * Global temperature
     * Negative emissions
     * Rest of world temperature
     * Tipping points
     * UK temperature
   * Global South Climate Database
 * Energy
   * Coal
   * Emissions
     * EU emissions
     * Global emissions
     * Rest of world emissions
     * UK emissions
   * Nuclear
   * Oil and gas
   * Renewables
   * Technology
 * Policy
   * China Policy
   * EU policy
   * International policy
   * Rest of world policy
   * UK policy
   * UN climate talks
     * COP21 Paris
     * COP22 Marrakech
     * COP23 Bonn
     * COP24 Katowice
     * COP25 Madrid
     * COP26 Glasgow
     * COP27 Sharm el-Sheikh
   * US Policy
 * In focus
   * Country profiles
   * Explainers
   * Factchecks
   * Features
   * Guest posts
   * Infographics
   * Interviews
   * Media analysis
   * Translations
   * Webinars
 * Daily Brief

Weather station at Krkonose National Park, Czech Republic Credit: Ivoha / Alamy
Stock Photo
GLOBAL TEMPERATURE
19 July 2017 13:31


EXPLAINER: HOW DATA ADJUSTMENTS AFFECT GLOBAL TEMPERATURE RECORDS

 * 
 * 
 * 
 * 
 * 

ZEKE HAUSFATHER

07.19.17

ZEKE HAUSFATHER

19.07.2017 | 1:31pm
Global temperatureExplainer: How data adjustments affect global temperature
records
 * 
 * 
 * 
 * 



Over the past two centuries, the times of day, locations and methods of
measuring temperature have all changed dramatically. For example, where once
researchers lowered buckets over the side of ships to collect water for
measuring, we now have a global network of automated buoys floating around the
oceans measuring the water directly.

This complicates matters for scientists putting together a long-term, consistent
estimate of how global temperatures are changing. Scientists must adjust the raw
data to take into account all the differences in how, when and where
measurements were taken.



These adjustments have long been a heated point of debate. Many climate sceptics
like to argue that scientists “exaggerate” warming by lowering past temperatures
and raising present ones.

Christopher Booker, a climate sceptic writing in the Sunday Telegraph in 2015,
called them “the greatest scientific scandal in history”. A new report from the
rightwing US thinktank, the Cato Institute, even claims that adjustments account
for “nearly all the warming” in the historical record.

But analysis by Carbon Brief comparing raw global temperature records to the
adjusted data finds that the truth is much more mundane: adjustments have
relatively little impact on global temperatures, particularly over the past 50
years.

In fact, over the full period when measurements are available, adjustments
actually have the net effect of reducing the amount of long-term warming that
the world has experienced.


RAW DATA SHOWS MORE GLOBAL WARMING

Land and ocean temperatures are adjusted separately to correct for changes to
measurement methods over time. All the original temperature readings from both
land-based weather stations and ocean-going ships and buoys are publically
available and can be used to create a “raw” global temperature record.

The figure below shows the global surface temperature record created from only
raw temperature readings with no adjustments applied (blue line). The red line
is the adjusted land and ocean temperature record produced using adjusted data
from the US National Oceanic and Atmospheric Administration (NOAA), with the
difference between the two in grey.



Global mean adjusted and raw surface temperature. See note at the end for
technical details on this analysis. Anomalies plotted with respect to a
1961-1990 baseline. Chart by Carbon Brief using Highcharts.

You can see that adjustments to the data have relatively little effect on global
temperatures after 1950. The rate of warming between 1950 and 2016 in the
adjusted data is just under 10% faster than the raw data, and only 4% faster
since the start of the modern warming period in 1970.

The adjustments that have a big impact on the surface temperature record all
occur before 1950. Here, past temperatures are adjusted up – significantly
reducing the warming over the past century. Over the full 1880-2016 period, the
adjusted data actually warms more than 20% slower than the raw data. The large
adjustments before 1950 are due almost entirely to changes in the way ships
measured temperatures (more on that later).


ADJUSTMENTS TO LAND TEMPERATURES

So, looking at data adjustments more closely, why and how are land-based
temperature measurements adjusted?

A single weather station will likely see many changes over the decades that it
is in use. Few stations remain in exactly the same place over very long periods,
with most stations experiencing at least one move to a new location. Most
stations have also changed the way they measure temperatures, transitioning from
liquid-in-glass thermometers to electronic instruments. Stations have often
changed the time of day they measure temperatures, and growing cities and urban
areas can introduce artificial warming in some stations. Very local factors,
such as trees growing over stations or poor station siting, can also cause
problems.

To correct for differences in a temperature record caused by these changes,
known as inhomogeneities, scientists employ an approach known as statistical
homogenization. They compare each station to all of its nearby neighbours and
look for changes that are local to one station, but not found at any others in
the area. Over long periods of time, climate changes are very rarely local, so
localised changes not seen at surrounding stations are most likely due to
something such as a station move or instrument change.

For example, if one station is warming over the course of a decade, while all
the surrounding stations are cooling, that station would be flagged as
“inhomogenous” and its record would be corrected to bring it back in line with
its neighbours.

Disruptions of station records associated with station moves, time of
observation changes, and even urbanisation tend to only affect one station in a
region at a time, and can be easily picked up by neighbour comparisons.

The figure below shows the net effect of all the adjustments to land stations to
the global land temperature record. Adjustments increase the overall land
temperature warming by 16% between 1880 and 2016. Most of this is concentrated
in the earlier part of the temperature record. Since 1970, adjustments only
increase warming by 3%.

Adjustments to land temperatures do have larger effects in some particular
regions – such as in the US and Africa – but these tend to average out when
looking at the global land surface record.




Global adjusted and raw land temperatures. Anomalies plotted with respect to a
1961-1990 baseline. Chart by Carbon Brief using Highcharts.

Scientists have gone to great lengths to test the methods they use to adjust
land stations to ensure that they are accurately detecting and correcting
problems without introducing spurious warming or cooling. This includes
benchmarking studies – testing their approach on data with different types of
errors added to it.

They have also set up a climate reference network in the US of perfectly sited
stations with high-accuracy sensors. Comparing the raw and adjusted stations to
this reference network,  scientists have shown that the adjustments
significantly improve the accuracy of the data.

While much has been made about adjustments to individual land stations that
increase warming, these are often extreme cases cherry-picked to make a point.
When adjustments to all stations are considered, just as many reduce warming as
increase warming, as shown in the figure below from NOAA.

Histogram of NOAA adjustments to land temperature stations outside the US in an
old (blue) and new (red) version of their adjustment algorithm. Details and
additional US figures can be found on the NOAA website.

Here, roughly half of all corrections reduce the temperature and half increase
it. For example, one station in Darwin, Australia has been adjusted to show more
warming to account for a station move and shelter change in the 1940s. Yet the
adjustment of another station – this time a station in Tokyo, Japan – has
reduced the warming it shows to correct for the urban heat island effect of an
expanding city.

Scientists have also worked to improve the number of land temperature records
available to use by collecting and digitising old temperature records from
around the world. New efforts such as the International Surface Temperature
Initiative (ISTI) and the Berkeley Earth Surface Temperature Project have worked
to increase the number of historical land stations available by around 500%,
compared to prior station collections, and provided better coverage of the
Earth’s regions, as shown in the figure below.

Number of land stations available in the old NOAA station collection (black) and
the new International Surface Temperature Initiative collection (red). Figure
from ISTI.


ADJUSTMENTS TO OCEAN TEMPERATURES

Improvements to temperature measurements aren’t limited to the land – perhaps
even more significant advances have come in how temperatures are measured in our
oceans.

The biggest adjustment by far is the switch from bucket-based measurements to
engine intakes in ships in the 1930s and 1940s. This is the “only one that
matters” globally, says Maynooth University researcher Dr Peter Thorne, who has
worked with NOAA to develop their ocean temperature record.

Prior to 1940, most ships measured temperatures by throwing a bucket overboard
into the water, pulling it up onto the deck by rope, and sticking a thermometer
in the bucket to measure the temperature of the water. The problem is that air
temperatures are often much warmer or colder than ocean temperatures. As the
bucket is slowly pulled up onto deck, the water will heat up or cool down.

During the 1930s and 1940s, most ships switched to measuring temperatures
through engine room intakes. Ships pull seawater in through the hull to cool the
engine and the temperature of the water was taken as it came in. This resulted
in temperature readings quite a bit different than when using buckets, since –
despite the fact that engine rooms are warm – the water had little time to warm
up or cool down before being measured.

The raw and adjusted ocean temperature records are shown in the figure below,
with the bucket adjustments quite prominent at around 0.3C.




Global adjusted and raw sea surface temperatures. Anomalies plotted with respect
to a 1961-1990 baseline. Chart by Carbon Brief using Highcharts.

The large pre-1940 bucket adjustments greatly reduce the long-term warming in
the record, resulting in 36% less warming since 1880 than in the raw temperature
data. In recent years, adjustments to ocean temperatures slightly increase the
rate of warming by around 4%.

Since 1990, the way that oceans temperatures are measured has changed once
again. While about 90% of measurements came from ships 20 years ago, today
almost 80% come from buoys floating in the ocean. These buoys are in direct
contact with the water and end up reading temperatures slightly lower than
measurements taken in engine room intakes.

To correct for a cool bias introduced by adding cooler buoy data to warmer ship
data, temperatures are adjusted slightly upwards for recent years. This fact
proved quite controversial with the publication of a paper by Tom Karl and
colleagues in 2015, but has since been validated by other studies. The net
effect of these buoy-related adjustments, however, is relatively small.


RECORDS FROM MANY DIFFERENT GROUPS

It’s also worth noting that adjustments to temperature records are not decided
by one single group of scientists. Rather, multiple different research teams
have independently created their own land and ocean temperature records.

While much of the underlying raw data is the same, each takes a somewhat
different approach to adjustments and how to deal with areas of the earth with
missing data. The resulting global temperature records from five different
groups, along with the raw data, are shown in the figure below.




Global mean surface temperatures from NASA, NOAA, Hadley/UEA, Berkeley Earth,
and Cowtan and Way. Anomalies plotted with respect to a 1961-1990 baseline.
Chart by Carbon Brief using Highcharts.

NOAA and NASA share the same adjustment approach for land and oceans, though
NASA applies an additional correction for urban heat islands that gives stations
in cities less weight. The record jointly produced by the UK Met Office Hadley
Centre and the University of East Anglia’s Climatic Research Unit has its own
approach of relying mostly on national meteorological offices to adjust the data
within their own countries. It also has its own separate ocean temperature
record with its own adjustment approach. The temperature record by researchers
Cowtan and Way simply use Hadley data with a different approach for areas with
missing data, such as the polar regions.

The Berkeley Earth Surface Temperature project, which was founded as an
independent non-governmental group to independently assess surface temperature
records, has its own unique approach for adjusting land records. This detects
problems at local stations and cuts the station record at the point where the
problem is found. Everything after that point is considered to be a new station.
For sea surface temperatures, Berkeley uses Hadley’s adjusted ocean record.


CHANGING VERSIONS OF TEMPERATURE DATASETS

Those sceptical of temperature adjustments have often tried to show their impact
by comparing older and newer versions of the same temperature record. The
problem with this approach is that it risks conflating changes in data
availability, methodology and adjustments.

However, even if different versions of prior records are compared, the changes
over time between records are generally relatively small. The charts below show
different versions of the NASA and Hadley/UEA datasets published over the past
30 years.




5-year running mean comparisons of past and current versions of the Hadley/UEA
record (top) and NASA record (bottom). Anomalies plotted with respect to a
1961-1990 baseline. Chart by Carbon Brief using Highcharts.

Subsequent updates to datasets after the mid-1990s are actually quite small and
mostly reflect factors such as increased station data availability in the Arctic
and recent adjustments such as the ship-buoy transition corrections. It’s only
when you compare them to global temperature estimates from the 1980s that larger
differences emerge.

This is because early 1980s estimates of global temperatures had much less data
to work with. Scientists had yet to undertake the painstaking work of collecting
and digitising much of the world’s temperature records from paper logbooks.

In 1981, for example, NASA relied on only a few hundred land stations almost
entirely in the Northern Hemisphere to estimate global temperatures. Their
temperature record did not even use any sea surface temperature data until the
1990s. Today, scientists have collected records from more than 32,000 land
stations and more than 1.2m observations of sea surface temperatures per year.

Both the number of stations included and the methodology used by global surface
temperature datasets have changed over time. Rather than compare different
versions of existing datasets, it is much simpler to analyse all the raw
temperature records available today and compare them to the adjusted data. This
lets scientists isolate just the effect of the adjustments.


CONCLUSION

With almost 200 years of raw data to work with, adjustments are a necessary part
of the methodology for scientists constructing long-term global temperature
records. But most of these adjustments are small and they have relatively little
impact on temperature records over the past few decades.

The most significant account for the shift from buckets to ship intakes in ocean
temperature records in the 1930s and 1940s, and these changes are
well-understood by scientists. And, contrary to popular belief, adjustments
actually reduce, rather than increase, the amount of warming experienced
globally over the past century.


METHODOLOGICAL FOOTNOTE

The global, land and ocean temperature records from raw and adjusted data shown
in the article were constructed as follows:

Land: Both raw and adjusted land temperature data was obtained from the Global
Historical Climatological Network Monthly Version 4. Stations records were
converted into anomalies with respect to a 1961-1990 baseline period. Stations
with fewer than 10 years overlap with the baseline period were discarded.
Stations were assigned to 5×5 latitude/longitude grid cells. Anomalies for each
month were averaged within each grid cell. A global land temperature estimate
was calculated by an area-weighted average of grid cells for each month.

Ocean: Raw ocean temperature records from ships and buoys are available from
ICOADS. For this analysis, an unadjusted gridded product provided by HadSST3 was
used. Adjusted ocean temperature records were taken from the ERSSTv4 gridded
product.

Global: Global land/ocean temperatures were estimated by weighted combination of
land and ocean temperature, with weights of 0.71 for ocean and 0.29 for land
representing their relative portion of the Earth’s surface.

Note: The author of this article was a member of the team that produced the
Berkeley Earth Surface Temperature project. In addition, he is the lead author
on the paper mentioned assessing the Karl et al 2015 buoy corrections and the
paper on US climate reference network comparisons.

Sharelines from this story
   
 * Explainer: How data adjustments affect global temperature records
   

Comments
View Comments (2 Comments) Close Comments


Expert analysis direct to your inbox.

Get a round-up of all the important articles and papers selected by Carbon Brief
by email. Find out more about our newsletters here.
By entering your email address you agree for your data to be handled in
accordance with our Privacy Policy.

Your data will be handled in accordance with our Privacy Policy.

Daily Briefing Weekly Briefing China Cropped


Published under a CC license. You are welcome to reproduce unadapted material in
full for non-commercial use, credited ‘Carbon Brief’ with a link to the article.
Please contact us for commercial use.

SECTIONS

 * Science
 * Energy
 * Policy
 * In Focus
 * China Briefing
 * Cropped

ABOUT

 * About Us
 * Contact Us
 * Newsletters
 * Privacy Policy
 * Cookie Policy
 * Comments Policy

SOCIAL

 * Twitter
 * LinkedIn
 * Facebook
 * Instagram
 * YouTube



--------------------------------------------------------------------------------

Published by Carbon Brief Ltd © 2022 - Company No. 07222041


Notifications