The Dependence of Northwest Pacific Tropical Cyclone Intensification Rates on Environmental Factors

<div>The frequency distribution of the three intensification categories (RI, NI, and SI) as a function of vertical wind shear (VWS, m s<sup>−1</sup>): (a) deep-layer shear <span class="nowrap"><svg height="12.1541pt" id="M46" style="vertical-align:-3.400761pt" version="1.1" viewbox="-0.0498162 -8.75334 60.4666 12.1541" width="60.4666pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M687 650H462V622C543 612 549 605 530 547C498 447 422 252 372 126H370C302 298 229 492 204 563C188 607 191 615 262 622V650H17V622C77 616 93 608 122 534C180 389 262 172 329 -11H360C436 196 541 450 568 516C606 605 619 614 687 622V650Z"></path></g><g transform="matrix(.013,0,0,-0.013,9.139,0)"><path d="M956 650H736V622C814 613 818 602 804 542C789 471 733 275 691 141H689C628 314 570 476 514 641H485C434 478 377 312 323 142H321C277 284 238 419 199 554C184 605 186 613 259 622V650H16V622C77 615 92 606 117 524C172 346 228 170 281 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360 217 360 144C360 69 312 23 252 23Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,50.885,3.132)"><path d="M158 548H390L417 615L410 623H122L83 318C105 326 143 337 185 337C296 337 350 275 350 188C350 116 308 42 225 42C164 42 122 74 100 93C90 101 82 99 72 92C60 82 51 68 50 59C48 46 52 38 66 24C82 9 125 -12 172 -12C225 -11 292 15 346 59C408 108 437 166 437 226C437 309 371 397 242 397C214 397 170 382 133 369L158 548Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,55.317,3.132)"><path d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g></svg>,</span> (b) upper-mid shear <span class="nowrap"><svg height="12.1541pt" id="M47" style="vertical-align:-3.400761pt" version="1.1" viewbox="-0.0498162 -8.75334 60.4666 12.1541" width="60.4666pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g 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174 128 313S152 598 243 598Z"></path></g></svg>,</span> (c) mid-low shear <span class="nowrap"><svg height="12.1541pt" id="M48" style="vertical-align:-3.400761pt" version="1.1" viewbox="-0.0498162 -8.75334 60.4666 12.1541" width="60.4666pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M687 650H462V622C543 612 549 605 530 547C498 447 422 252 372 126H370C302 298 229 492 204 563C188 607 191 615 262 622V650H17V622C77 616 93 608 122 534C180 389 262 172 329 -11H360C436 196 541 450 568 516C606 605 619 614 687 622V650Z"></path></g><g transform="matrix(.013,0,0,-0.013,9.139,0)"><path d="M956 650H736V622C814 613 818 602 804 542C789 471 733 275 691 141H689C628 314 570 476 514 641H485C434 478 377 312 323 142H321C277 284 238 419 199 554C184 605 186 613 259 622V650H16V622C77 615 92 606 117 524C172 346 228 170 281 -11H312C363 151 419 312 475 488H477C528 343 597 150 652 -11H683C765 269 826 458 848 522C878 605 887 613 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Advances in Meteorology

fig8

Figure 8

Figure 8: The Dependence of Northwest Pacific Tropical Cyclone Intensification Rates on Environmental Factors 