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<p>In eastern Mediterranean sediments, the titanium-to-aluminum ratio (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="64481113532f6f6aaedbbc4986bb9f3d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00004.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00004.png"/></svg:svg></span></span>) captures relative variability in eolian to river-derived material and predominantly integrates climate signals over the Saharan and Sahel regions. Long <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="4aafc6daada45b9df6f352cb7a5a40e6"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00005.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00005.png"/></svg:svg></span></span> time series can, therefore, provide valuable records of North African humidity and aridity changes. X-ray fluorescence core scanning (XRF-CS) can generate near-continuous <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="c44275bf989596cb7d53e749a1d53c67"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00006.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00006.png"/></svg:svg></span></span> records with relatively modest effort and in an acceptable amount of time, provided that accurate <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="c8acaaab669fe2f175ebd65fad05866e"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00007.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00007.png"/></svg:svg></span></span> values are acquired. Calibration of raw XRF-CS data to those of established analytical methods is an important pathway for obtaining the required accuracy. We assess how to obtain reliable XRF-CS <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="7a02d7ed88fae10195c9dfe104c07956"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00008.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00008.png"/></svg:svg></span></span> calibration by using different calibration reference sample sets for a long sediment record from ODP Site 967 (eastern Mediterranean Sea). The accuracy of reference concentrations and the number of reference samples are important for reliable calibration. Our continuous <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="17bdb234fe90d2691091a16e5ea88534"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00009.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00009.png"/></svg:svg></span></span> record allows detailed time series analysis over the past 3 Myr. Near-direct control of low-latitude insolation on the timing and amplitude of North African aridity and humidity is observed from 3 to <span class="inline-formula">∼</span> 1.2 Ma. In our <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M10" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ti</mi><mo>/</mo><mi mathvariant="normal">Al</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="27pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="ccff6f3b90c38db22f007813de178917"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cp-18-2509-2022-ie00010.svg" width="27pt" height="14pt" src="cp-18-2509-2022-ie00010.png"/></svg:svg></span></span> record, most arid North African intervals (i.e., with the longest period and highest amplitude) occur after the mid-Pleistocene transition (MPT; <span class="inline-formula">∼</span> 1.2–0.7 Ma), when ice ages intensified. We also observe a subdued relationship between low-latitude insolation and North African climate after the MPT. These findings support the growing consensus that African climate became more sensitive to remote high-latitude climate when a threshold ice volume was reached during the MPT.</p>