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South Pacific convergence zone

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224:. During El Niño or warm-phase conditions, the SPCZ typically shifted northeastward with dryer conditions on islands to the southwest, in agreement with observations. Conversely, a southwestward shift in rainfall accompanied La Niña or cold-phase events in the simulations. Widlanksy et al. (2012) argued the sea surface temperature biases in models created uncertainty in the rainfall projections and produce what has been named “the double ITCZ problem”. The impact of sea surface temperature bias was further investigated by using uncoupled atmospheric models with prescribed sea surface temperatures, and those 3 models each with differing complexity showed less severe double ITCZ bias than the ensemble of coupled models. 197:. Coral isotope measurements provide information on both sea surface temperature and sea surface salinity, so they can indicate times of increased or decreased temperature and/or precipitation associated with changes in the position of the SPCZ. Their coral oxygen isotope index indicated an eastward shift of the decadal mean position of the SPCZ since the mid 1800s. A shift of the SPCZ in this direction suggests there were more La Niña-like or cold-phase conditions in the Pacific, during this period, often called the 181:(ENSO) and can also describe movements of the position of the SPCZ. Negative SOI index values are associated with warm-phase or El Niño-like conditions and a northeastward displacement of the SPCZ. Positive SOI index values, on the other hand, describe cold-phase or La Niña-like conditions and a southwestward displacement of the SPCZ. 184:
Determining the position of the SPCZ over longer timescales in the past (pre-20th century) has been studied using coral records of the southwest Pacific. Linsley et al. (2006) reconstructed sea-surface temperature and sea surface salinity in the southwest Pacific starting circa 1600CE by measuring
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to the south meet with the semipermanent easterly flow from the eastern South Pacific anticyclone. The SPCZ exists in summer and winter but can change its orientation and location. It is often distinct from the ITCZ over Australia, but at times they become one continuous
123:. Thunderstorm activity, or convection, within the band is dependent upon the season, as the more equatorward portion is most active in the Southern Hemisphere summer, and the more poleward portion is most active during transition seasons of fall and spring. The 172:
and night marine air temperature to determine how the SPCZ varies with the IPO. When the IPO index has negative temperature anomalies, the SPCZ is displaced southwest and moves northeastward when the IPO index has positive temperature anomalies. The
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The climatological position can be estimated by computing its mean position over 30 or more years. There are several metrics to measure the position of the SPCZ. The location of maximum rainfall, maximum of low level
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At its southeast edge, the circulation around the feature forces a salinity gradient in the ocean, with fresher and warmer waters of the western Pacific lying to its west. Cooler and saltier waters lie to its east.
62:. The SPCZ can affect the precipitation on Polynesian islands in the southwest Pacific Ocean, so it is important to understand how the SPCZ behaves with large-scale, global climate phenomenon, such as the ITCZ, 468: 208:) and IPO strongly influence the SPCZ latitude, but farther east only ENSO is a significant factor. Only near 170 W is there any indication of an interaction between the two factors. 58:. It is considered the largest and most important piece of the ITCZ, and has the least dependence upon heating from a nearby landmass during the summer than any other portion of the 303: 465: 220:
of differing complexity to simulate rainfall bands in the southwest Pacific and see how the magnitude and areal extent was affected by the SPCZ and
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Besides observations of the SPCZ and movement in its position, there have been modelling studies as well. Widlansky et al. (2012) used a number of
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Research into SPCZ movements of the 20th century are linked to changes in the IPO and ENSO. Folland et al., 2002 defined an index to describe the
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The IPO and ENSO can interact together to produce changes in the position of the SPCZ. West of about 140 W, both ENSO (measured with
54:(ITCZ) which lies in a band extending east–west near the Equator but can be more extratropical in nature, especially east of the 480: 242: 178: 63: 300: 148:(OLR) are four indicators of the SPCZ axis. Figure 1 shows qualitative agreement between all of these SPCZ indicators. 564: 165: 96: 67: 569: 51: 559: 554: 498:"Relative influences of the Interdecadal Pacific Oscillation and ENSO in the South Pacific Convergence Zone" 360:"Relative influences of the Interdecadal Pacific Oscillation and ENSO in the South Pacific Convergence Zone" 201:. Additional paleoclimate studies are still needed in order to test the reliability of these coral results. 145: 71: 448:, Karl Stein, Shayne McGregor, Niklas Schneider, Matthew H. England, Matthieu Lengaigne, and Wenju Cai. 323:
An observational study of the South Pacific Convergence Zone using satellite and model re-analysis data
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The position of the SPCZ can change on seasonal, interannual, and possibly longer timescales.
531: 393: 287: 252: 509: 422: 371: 491: 353: 8: 513: 375: 321: 42:, is a band of low-level convergence, cloudiness and precipitation extending from the 476: 177:(SOI) is a metric for describing warm- and cold-phase conditions associated with the 46:
at the maritime continent south-eastwards towards French Polynesia and as far as the
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Tracking the extent of the South Pacific Convergence Zone since the early 1600s.
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shifts east or west depending on the existence of El Niño, or the phase of
120: 47: 522: 497: 384: 359: 83: 331: 92: 190: 421:, Peter B. deMenocal, Gerard M. Wellington, and Stephen S. Howe. 186: 104: 141: 116: 112: 466:
Tropical textbook : from trade winds to cyclone (2 vol)
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Changes in South Pacific rainfall bands in a warming climate
144:, maxima of the 500 hPa vertical motion, and the minimum in 221: 194: 128: 108: 82:
The SPCZ occurs where the southeast trades from transitory
475:, 897 pp., Florent Beucher, 25 mai 2010, Météo-France, 417:Braddock K. Linsley, Alexey Kaplan, Yves Gouriou, 546: 288:Movement of the South Pacific Convergence Zone. 326:(PhD dissertation). Texas A&M University. 99:conditions. It generally stretches from the 536:: CS1 maint: multiple names: authors list ( 398:: CS1 maint: multiple names: authors list ( 440: 438: 151: 134: 91:. The location of the SPCZ is affected by 50:(160W, 20S). The SPCZ is a portion of the 521: 413: 411: 409: 383: 349: 347: 345: 343: 341: 435: 185:the oxygen isotopic composition of four 227: 14: 547: 406: 338: 319: 211: 24: 25: 581: 273: 166:Interdecadal Pacific oscillation 97:Interdecadal Pacific oscillation 68:Interdecadal Pacific oscillation 320:Cocks, Stephen Brenton (2003). 301:South Pacific convergence zone. 159: 492:C. K. Folland, J. A. Renwick, 354:C. K. Folland, J. A. Renwick, 313: 293: 280: 52:Intertropical Convergence Zone 32:South Pacific Convergence Zone 18:South Pacific Convergence Zone 13: 1: 268: 502:Geophysical Research Letters 364:Geophysical Research Letters 243:El Niño–Southern Oscillation 179:El Niño–Southern Oscillation 64:El Niño–Southern Oscillation 7: 236: 146:outgoing longwave radiation 77: 72:Pacific decadal oscillation 10: 586: 286:E. Linacre and B. Geerts. 206:Southern Oscillation Index 175:Southern Oscillation Index 299:Glossary of Meteorology. 44:Western Pacific Warm Pool 565:Regional climate effects 485: 432:Retrieved on 2006-11-26. 310:Retrieved on 2006-11-26. 290:Retrieved on 2006-11-26. 152:Changes in SPCZ position 70:(IPO), a portion of the 496:, A. B. Mullan (2002). 358:, A. B. Mullan (2002). 170:sea surface temperature 135:Measuring SPCZ position 56:International Date Line 444:Matthew J. Widlansky, 38:), a reverse-oriented 27:Seasonal storm pattern 570:Physical oceanography 253:Tropical cyclogenesis 560:Atmospheric dynamics 555:Tropical meteorology 523:10.1029/2001GL014201 385:10.1029/2001GL014201 228:Related oceanography 514:2002GeoRL..29.1643F 376:2002GeoRL..29.1643F 189:coral records from 89:zone of convergence 428:2011-06-06 at the 306:2007-09-30 at the 508:(13): 21–1–21–4. 481:978-2-11-099391-5 370:(13): 21–1–21–4. 212:Climate modelling 16:(Redirected from 577: 541: 535: 527: 525: 461: 452: 442: 433: 415: 404: 403: 397: 389: 387: 351: 336: 335: 317: 311: 297: 291: 284: 258:Tropical cyclone 125:convergence zone 21: 585: 584: 580: 579: 578: 576: 575: 574: 545: 544: 529: 528: 488: 459: 456: 455: 446:Axel Timmermann 443: 436: 430:Wayback Machine 416: 407: 391: 390: 352: 339: 318: 314: 308:Wayback Machine 298: 294: 285: 281: 276: 271: 263:Coral bleaching 239: 230: 214: 162: 154: 137: 101:Solomon Islands 80: 28: 23: 22: 15: 12: 11: 5: 583: 573: 572: 567: 562: 557: 543: 542: 494:M. J. Salinger 487: 484: 471:2012-12-16 at 463: 462: 454: 453: 434: 405: 356:M. J. Salinger 337: 312: 292: 278: 277: 275: 274:World Wide Web 272: 270: 267: 266: 265: 260: 255: 250: 248:Monsoon trough 245: 238: 235: 229: 226: 218:climate models 213: 210: 199:Little Ice Age 161: 158: 153: 150: 136: 133: 79: 76: 60:monsoon trough 40:monsoon trough 26: 9: 6: 4: 3: 2: 582: 571: 568: 566: 563: 561: 558: 556: 553: 552: 550: 539: 533: 524: 519: 515: 511: 507: 503: 499: 495: 490: 489: 483: 482: 478: 474: 473:archive.today 470: 467: 458: 457: 451: 447: 441: 439: 431: 427: 424: 420: 414: 412: 410: 401: 395: 386: 381: 377: 373: 369: 365: 361: 357: 350: 348: 346: 344: 342: 333: 329: 325: 324: 316: 309: 305: 302: 296: 289: 283: 279: 264: 261: 259: 256: 254: 251: 249: 246: 244: 241: 240: 234: 225: 223: 219: 209: 207: 202: 200: 196: 193:and two from 192: 188: 182: 180: 176: 171: 167: 157: 149: 147: 143: 132: 130: 126: 122: 121:thunderstorms 118: 114: 110: 106: 102: 98: 94: 90: 85: 75: 73: 69: 65: 61: 57: 53: 49: 45: 41: 37: 33: 19: 532:cite journal 505: 501: 464: 419:Jim Salinger 394:cite journal 367: 363: 322: 315: 295: 282: 231: 215: 203: 183: 163: 160:Observations 155: 138: 84:anticyclones 81: 48:Cook Islands 35: 31: 29: 460:(in French) 168:(IPO) with 142:convergence 549:Categories 332:1969.1/374 269:References 66:, and the 191:Rarotonga 469:Archived 426:Archived 304:Archived 237:See also 103:through 78:Position 510:Bibcode 372:Bibcode 187:Porites 105:Vanuatu 479:  115:, and 486:Print 117:Tonga 113:Samoa 538:link 477:ISBN 400:link 222:ENSO 195:Fiji 129:ENSO 109:Fiji 95:and 93:ENSO 36:SPCZ 30:The 518:doi 380:doi 328:hdl 551:: 534:}} 530:{{ 516:. 506:29 504:. 500:. 437:^ 408:^ 396:}} 392:{{ 378:. 368:29 366:. 362:. 340:^ 131:. 111:, 107:, 74:. 540:) 526:. 520:: 512:: 402:) 388:. 382:: 374:: 334:. 330:: 34:( 20:)

Index

South Pacific Convergence Zone
monsoon trough
Western Pacific Warm Pool
Cook Islands
Intertropical Convergence Zone
International Date Line
monsoon trough
El Niño–Southern Oscillation
Interdecadal Pacific oscillation
Pacific decadal oscillation
anticyclones
zone of convergence
ENSO
Interdecadal Pacific oscillation
Solomon Islands
Vanuatu
Fiji
Samoa
Tonga
thunderstorms
convergence zone
ENSO
convergence
outgoing longwave radiation
Interdecadal Pacific oscillation
sea surface temperature
Southern Oscillation Index
El Niño–Southern Oscillation
Porites
Rarotonga

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