關於地球未解之謎的十大奇怪解釋(下)

Wildfires Always Cause Global Warming?

5.野火總會引起溫室效應嗎?

Conventional wisdom tells us that fires transmute trees and related foliage into pollution, in the form of greenhouse gasses like carbon dioxide.

社會傳統的經驗告訴我們：烈火能夠把樹木和樹葉轉化爲污染物，例如二氧化碳之類的溫室氣體。

But the disintegration of large swaths of organic material can be beneficial as well. Clearing the shrubbery increases local albedo, or reflective value. The amount of sunlight bounced back out into space increases. This cooling is observed in boreal biomes. However, the immediate surge in burning pollution that accompanies a major fire does contribute to warming. And as the black ash falls back to Earth, it blankets the region, increasing absorption of solar radiation. But after the ashes clear, it's smooth t, a snowy and highly reflective surface is revealed to the Sun, and solar rays are reflected back into the cosmos. Then, new deciduous species replace the pre-fire conifers. And their young, glossy leaves offer additional reflective surfaces to thwart the Sun. In winter, the newcomers shed their leaves, unlike their piney predecessors, and a mirror-like terrain once again reveals yes, the initial fire is kind of an environmental hazard. But scientists predict that in only eight decades, the effects reverse. At this point, the deleterious effects of the fire will have been undone, yet local cooling will persist.

但是大量有機物的分解卻是有益的。灌木叢被清理之後，當地地表的反射率或是反射值提高。反射回太空的日照量也隨之增加。這種冷卻現象是在寒帶生物羣落中觀察到的。然而，重大火災產生的污染物激增，確實加重了溫室效應。隨着火災產生的灰屑落在大地上，大地就好像披上了一層黑色毛毯，隨即增強了吸收太陽輻射的能力。但是當這些灰燼消失後，一切順利進行。首先,蓋滿大雪的地表反射率很高，袒露在太陽之下，太陽光線就被反射回了太空。然後，新的落葉林就代替了大火之前的針葉林。它們新生的叢叢葉子對陽光的反射率更高，進一步阻擋了陽光。冬天，這些新生的樹木葉子脫落，不像之前那些松柏類植物，於是鏡子一樣的地表就再次暴露在陽光之下。最初的大火確實是一種自然災害。但是科學家們預測，僅在八十年內這種影響就會逆轉。在這一點上，火災造成的毀滅性後果將被消除，而局部氣溫降低則會持續。

's Causing The Global Warming Hiatus?

4.爲何全球變暖中斷？

Global temperatures increased at high rates in the 20th century, but since 1998, there's been an unexpected lull. This has inspired optimism in the wasteful and righteousness in climate change deniers. To scientists, the decreased global warming rates are suspicious.

20世紀全球氣溫一直呈快速增長趨勢，但自1998年以來卻意想不到地穩定。這一現象支持浪費，否認了氣候變化，讓持這類觀點的人樂觀起來。科學家稱全球變暖速度減緩這一點十分可疑。

It turns out that we're in the eye of the environmental tornado. The Pacific Ocean is doing us a huge favor by dissipating large chunks of solar radiation into its watery bosom, part of a natural cycle played out over tiny geological timeframes. The global warming hiatus—now seen as more of a “false pause”—started in the late '90s. This date syncs with the back end of the El Nino warming event of 1997–1998. The Pacific Ocean cycles through its hot and cold phases for 16-20 years, suggesting a return to warmer waters any day now. Sadly, the intermittent periods of calm won't do much to buck long-term trends. But at least now we know what's happening.

環境就像龍捲風，而我們正處於風眼中。太平洋幫了我們一個大忙，吸收了大量太陽輻射，在極短的地質時期內進行着部分自然循環。開始於上世紀90年代的全球變暖中斷了，現在多被視爲“虛假暫停”。中斷時間與1997-1998厄爾尼諾引發氣候變暖事件的後段時期相吻合。太平洋水溫冷熱變化每16-20年循環一次，這意味着現階段它會隨時回暖。可惜的是，斷續出現的穩定對逆轉長期以來變暖的趨勢影響不大。但至少現在我們知道到底發生了什麼。

Do The Tectonic Plates Slide On?

3.什麼支撐着板塊漂移？

The theory of plate tectonics has been generally accepted for a while now, but it's never been clear what the continental slabs are sliding upon. To find out, researchers in New Zealand used one of the oldest scientific methods known to man: explosions.

目前，板塊構造理論得到公認已有一段時間了，但人們卻從未明確漂移的大陸板塊下面藏着什麼。爲了找到答案，新西蘭研究人員使用了一種人類已知最古老的科學方法：爆炸。

Seismic measurements are usually revealed by earthquakes. But Kiwi researchers didn't have time to wait for natural tremors, so they made their own. The team ventured to the southern tip of New Zealand's North Island and poured explosive slurry into a series of 50-meter-deep (160 ft), steel-insulated bore holes. The holes were drilled across a major subduction zone, where the Pacific plate joints the Australian plate. The explosion produced a downward-traveling earthquake and teased some telltale jiggles out of the crust. They found that the lithosphere (the crust) slides along a 5-kilometer-thick (3 mi) conveyor formed of a lubricating, jelly-like rock mixture. Officially the lithosphere asthenosphere boundary (LAB), this glorified Earth-lube disconnects the crust from the mantle and provides a cushy platform for continental shifts. It's believed the LAB's squishiness is a result of increased water or magma content. Surprisingly, a tiny increase of 1–2 percent compared to the crust is enough to form the gelatinous boundary. However, researchers still don't know whether the plates are pushed or pulled along the syrupy effluence and if this material is present underneath all plates. Whether a race of malefic mole men is implicated remains a mystery as well.

通常地震會留給我們很多相關數據。但是新西蘭研究人員沒有時間等地殼自然震動，因此他們製造了地震。研究隊冒險來到了新西蘭北島的南端，並將爆炸性漿液倒入許多50米（160英尺）深的鋼製隔熱鑽孔中。這些孔分佈在一個主要的俯衝帶，即太平洋板塊和澳大利亞板塊的接合處。爆炸產生了向下傳導的地震，引起地殼輕微晃動。他們發現，果凍狀的岩石混合物形成了一條5公里（3英里）厚的傳送帶，岩石圈（地殼）便隨着傳送帶滑動。正式的說法是，岩石圈軟流圈邊界（LAB）是重要的地球潤滑油，它隔開了地幔與地殼，併爲大陸漂移提供了一個方便的平臺。他們相信軟流圈邊界如此柔軟是水或岩漿增加的結果。令人驚訝地是，地殼增加1-2％的微量就足以形成凝膠狀邊界。然而，研究人員仍然不知道板塊是否隨着岩漿流動而分離或擠壓，這種物質又是否存在於所有板塊之下。至於是否涉及邪惡的鼴鼠人自然還是一團謎。

's Happening With Earth's Core?

2.地心在發生着什麼？

If finding a lubricating belt of tectonic sludge wasn't exciting enough, collaborators from the University of Illinois and Nanjing University have discovered Earth's second core. This breaking seismic research shows that Earth's innermost core is, in fact, Earth's second-innermost core. And the smaller sphere roiling within it sits mysteriously on its side, with its constituent iron crystals aligned east to west (as opposed to north to south).

如果地層裏的污泥潤滑帶還不夠震撼人心，那麼這一定可以：伊利諾伊大學和南京大學組成的研究合作團隊發現了地球的第二個核心。這項破天荒的地理髮現表明，最裏邊的地核實際上是地球的第二個核心。較小的核心在外核內旋轉，奇怪的是其位置始終偏向一方，而組成它的鐵晶粒由東到西連成了一條線（與從北向南相反）。

Obviously, a discovery of this magnitude deserves the good champagne. The additional core reveals Earth as a complicated, planetary onion full of inner tumult. The newly observed core churns against an outer shell of molten iron alloys as it steadily grows larger, at less than 1 millimeter a new core is also geologically akin to a time capsule. Researchers estimate that it solidified 500 million–1.5 billion years ago. That's not too long ago, on a global timescale 4.5 billion years long. Some major primeval event or catastrophe must have befallen the core soon after its birth, which would explain its sideways orientation.

顯然，這項重大發現值得我們舉杯同慶。第二地心揭示了地球是一個複雜的，像洋蔥一樣的行星，內部充滿摩擦。新發現的第二地心在外殼內轉動，而其熔融鐵合金外殼正以小於每年1毫米的速度穩步變大。第二地心類似地質上的一個時間囊。研究人員估計，它於5億至15億年前凝固成形。相對於地球45億年之久的歷史來說，這並不能算是很久以前。地心形成後不久，很可能發生了什麼大事或災難，這就可以解釋爲什麼地心偏向一邊。

Causes The Theta Aurora?

1.θ極光是怎樣形成的？

The theta aurora, named for its resemblance to the eponymous Greek letter, is an oval-shaped region of electromagnetic activity at the edge of Earth and space. It cannot be seen from the ground, and its existence was undetermined until space-age observations let us view the Earth from an external vantage point.

θ極光的名字源於和它外形相似的同名希臘字母，它出現在地球和太空的邊緣，是電磁活動的一片橢圓形區域。人們從地面上是看不到它的，它的出現也具有不確定性，直到太空時代的觀察結果讓我們可以借用外太空的有利位置一睹地球的風采。

Unlike the regular auroras popularized on postcards and such, the cosmic mechanisms that birth theta aurora outbursts were poorly understood. One possible explanation credits unusually hot globules of plasma crashing against our magnetosphere. Then combined satellite data fingered another culprit: funneled solar winds and magnetic mirrors (when ions bounce from high-density to low-density fields) appears the theta aurora is caused by plasma confined within enclosed fields. The charged particles are heated and bounce against closed lines as if trapped inside a giant, magnetic bouncy house. This explanation differs from the original supposition that the theta was caused directly by sweeping solar winds against our planet's magnetic mane.

θ極光並不像那種印在明信片上的普通極光，對於突然誕生θ極光的宇宙機制，人們還不是很清楚。一種可能的解釋是，它是由極其灼熱的等離子球撞擊地球磁層而產生的。組合衛星數據找到了另一罪魁禍首：地球磁場漏斗狀的太陽風和磁鏡（當離子從高密度地帶彈到低密度地帶的時候）。這樣看來，θ極光是因爲等離子體在封閉環境中活動受限而形成的。這些帶電粒子溫度很高，在閉合線中彈跳，就好像被困在一個巨大的，有磁力的的彈性房子裏。這種解釋有別於最初的假設，即θ極光是由太陽風掃過地球磁場直接產生的。

翻譯:步懶懶6+5 來源:前十網