[简答题]影响热对流的因素有哪些？

案例二
背景：
某建筑公司承建了一地处繁华市区的带地下车库的大厦工程，工程紧邻城市主要干道，施工现场狭窄，施工现场入口处设立了“五牌”和“两图”。工程主体9层，地下3层，建筑面积20000m²，基础开挖深度12m，地下水位3m。大厦212层室内采用天然大理石饰面，大理石饰面板进场检查记录如下：天然大理石建筑板材，规格：600mm×450mm，厚度18mm，一等品。2005年6月6日，石材进场后专业班组就开始从第12层开始安装。为便于灌浆操作，操作人员将结合层的砂浆厚度控制在18mm，每层板材安装后分两次灌浆。
建筑防水施工中发生如下事件：
事件一：地下室外壁防水混凝土施工缝有多处出现渗漏水；
事件二：屋面卷材防水层多处起鼓。
装饰装修工程中发生了如下事件：
2005年6月6日，专业班组请项目专职质检员检验12层走廊墙面石材饰面，结果发现局部大理石饰面产生不规则的花斑，沿墙高的中下部位空鼓的板块较多。
问题：

The world’s oceans have warmed 50 percent faster over the last 40 years than previously thought due to climate change, Australian and US climate researchers reported Wednesday. Higher ocean temperatures expand the volume of water, contributing to a rise in sea levels that is covering small island nations and threatening to destroy the low-lying, densely-populated low regions around the globe.
The study, published in the British journal Nature, adds to a growing scientific chorus of warnings about the pace and consequences rising oceans. It also serves as a corrective to a massive report issued last year by the Nobel-winning UN Intergovernmental Panel on Climate Change (IPCC), according to the authors.
Rising sea levels are driven by two things: the thermal expansion of sea water, and additional water from melting sources of ice. Both processes are caused by global warming. The ice sheet that sits atop Greenland, for example, contains enough water to raise wo
A. The warming of the world’s oceans is not a threat.
B. That not enough is being done about global warming.
C. There is a puzzling gap between the model and observations.
D. Ocean waters have warmed faster than scientists had previously thought.