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<p><span id="page3278"/>Following the release of the version 4 Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) data products from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) mission, a new version 4 (V4) of the CALIPSO Imaging Infrared Radiometer (IIR) Level 2 data products has been developed. The IIR Level 2 data products include cloud effective emissivities and cloud microphysical properties such as effective diameter (<span class="inline-formula"><i>D</i>_e</span>) and water path estimates for ice and liquid clouds. This paper (Part II) shows retrievals over ocean and describes the improvements made with respect to version 3 (V3) as a result of the significant changes implemented in the V4 algorithms, which are presented in a companion paper (Part I). The analysis of the three-channel IIR observations (08.65, 10.6, and 12.05 <span class="inline-formula">µ</span>m) is informed by the scene classification provided in the V4 CALIOP 5 km cloud layer and aerosol layer products. Thanks to the reduction of inter-channel effective emissivity biases in semi-transparent (ST) clouds when the oceanic background radiance is derived from model computations, the number of unbiased emissivity retrievals is increased by a factor of 3 in V4. In V3, these biases caused inconsistencies between the effective diameters retrieved from the <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">10</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="33pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="58d82d2473b82c7d1ca1e48acb4864df"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00001.svg" width="33pt" height="14pt" src="amt-14-3277-2021-ie00001.png"/></svg:svg></span></span> (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><msub><mi mathvariant="italic">β</mi><mi mathvariant="normal">eff</mi></msub><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">10</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="49pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="a96628ad84bcfe0a2f0c42919e3f61d7"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00002.svg" width="49pt" height="14pt" src="amt-14-3277-2021-ie00002.png"/></svg:svg></span></span> <span class="inline-formula">=</span> <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow><msub><mi mathvariant="italic">τ</mi><mrow><mi>a</mi><mo>,</mo><mn mathvariant="normal">12</mn></mrow></msub><mo>/</mo><msub><mi mathvariant="italic">τ</mi><mrow><mi>a</mi><mo>,</mo><mn mathvariant="normal">10</mn></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="50pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="292d90a69555f33f33a16533070481f2"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00003.svg" width="50pt" height="15pt" src="amt-14-3277-2021-ie00003.png"/></svg:svg></span></span>) and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">08</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="33pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="145a84a709c6a0d99d7b40d087e360b2"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00004.svg" width="33pt" height="14pt" src="amt-14-3277-2021-ie00004.png"/></svg:svg></span></span> (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><msub><mi mathvariant="italic">β</mi><mi mathvariant="normal">eff</mi></msub><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">08</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="49pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="ecd72137a86e1377beb9153497e202d5"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00005.svg" width="49pt" height="14pt" src="amt-14-3277-2021-ie00005.png"/></svg:svg></span></span> <span class="inline-formula">=</span> <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M10" display="inline" overflow="scroll" dspmath="mathml"><mrow><msub><mi mathvariant="italic">τ</mi><mrow><mi>a</mi><mo>,</mo><mn mathvariant="normal">12</mn></mrow></msub><mo>/</mo><msub><mi mathvariant="italic">τ</mi><mrow><mi>a</mi><mo>,</mo><mn mathvariant="normal">08</mn></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="50pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="fcd47eb9dae926be9d8c6e12dbf5fb5a"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00006.svg" width="50pt" height="15pt" src="amt-14-3277-2021-ie00006.png"/></svg:svg></span></span>) pairs of channels at emissivities smaller than 0.5. In V4, microphysical retrievals in ST ice clouds are possible in more than 80 % of the pixels down to effective emissivities of 0.05 (or visible optical depth <span class="inline-formula">∼0.1</span>). For the month of January 2008, which was chosen to illustrate the results, median ice <span class="inline-formula"><i>D</i>_e</span> and ice water path (IWP) are, respectively, 38 <span class="inline-formula">µ</span>m and 3 g m<span class="inline-formula">⁻²</span> in ST clouds, with random uncertainty estimates of 50 %. The relationship between the V4 IIR <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M15" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">10</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="33pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="a86f6a8cc8c2af3787df0eec3a7cf4e7"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00007.svg" width="33pt" height="14pt" src="amt-14-3277-2021-ie00007.png"/></svg:svg></span></span> and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M16" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">08</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="33pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="b019d864e3dfeff2f32ea7033ba2b16e"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00008.svg" width="33pt" height="14pt" src="amt-14-3277-2021-ie00008.png"/></svg:svg></span></span> microphysical indices is in better agreement with the “severely roughened single column” ice habit model than with the “severely roughened eight-element aggregate” model for 80 % of the pixels in the coldest clouds (<span class="inline-formula"><i>&lt;</i>210</span> K) and 60 % in the warmest clouds (<span class="inline-formula"><i>&gt;</i>230</span> K). Retrievals in opaque ice clouds are improved in V4, especially at night and for <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M19" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">12</mn><mo>/</mo><mn mathvariant="normal">10</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="33pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="2e7766845cc574a618d486a00fc9763b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-3277-2021-ie00009.svg" width="33pt" height="14pt" src="amt-14-3277-2021-ie00009.png"/></svg:svg></span></span> pair of channels, due to corrections of the V3 radiative temperature estimates derived from CALIOP geometric altitudes. Median ice <span class="inline-formula"><i>D</i>_e</span> and IWP are 58 <span class="inline-formula">µ</span>m and 97 g m<span class="inline-formula">⁻²</span> at night in opaque clouds, with again random uncertainty estimates of 50 %. Comparisons of ice retrievals with Moderate Resolution Imaging Spectroradiometer (MODIS)/Aqua in the tropics show a better agreement of IIR <span class="inline-formula"><i>D</i>_e</span> with MODIS visible–3.7 <span class="inline-formula">µ</span>m than with MODIS visible–2.1 <span class="inline-formula">µ</span>m in the coldest ST clouds and the opposite for opaque clouds. In prevailingly supercooled liquid water clouds with centroid altitudes above 4 km, retrieved median <span class="inline-formula"><i>D</i>_e</span> and liquid water path are 13 <span class="inline-formula">µ</span>m and 3.4 g m<span class="inline-formula">⁻²</span> in ST clouds, with estimated random uncertainties of 45 % and 35 %, respectively. In opaque liquid clouds, these values are 18 <span class="inline-formula">µ</span>m and 31 g m<span class="inline-formula">⁻²</span> at night, with estimated uncertainties of 50 %. IIR <span class="inline-formula"><i>D</i>_e</span> in opaque liquid clouds is smaller than MODIS visible–2.1 <span class="inline-formula">µ</span>m and visible–3.7 <span class="inline-formula">µ</span>m by 8 and 3 <span class="inline-formula">µ</span>m, respectively.</p>