Now suppose the same parcel in the previous question was moist (saturated) instead of dry, but still had a temperature of 6°C at 1000 meters. If it sinks to the surface, it will have a temperature of:

Question

BlackTom AI · Accepted Answer

Question restatement: The parcel is moist (saturated) at 6°C and 1000 meters, then sinks to the surface. What would its temperature be at the surface?

Option 1: 16°C. This would imply a temperature increase of 10°C during the descent of 1 km, which is inconsistent with typical descending lapse rates. In practice, moist adiabatic processes warm the parcel as it sinks, but the expected warming over 1 km near these conditions is around 5–6°C, not as high as 10°C, so 16°C overstates the heating.

Option 2: 0°C. This would require the parcel to cool by 6°C during the descent, which contradicts the basic idea of adiabatic compression heating when a parcel sinks (and the moist lapse rate in descent tends to increase temperature, not decrease it). It misapplies the direction of temperature change for a sinking parcel.

Option 3: 12°C. This value aligns with the expected warming from moist (saturated) adiabatic descent over roughly 1 kilometer, where the moist adiabatic lapse rate (about 5–6°C per kilometer in many tropospheric conditions) raises the temperature from 6°C at 1000 m to around 11–12°C at the surface. Given the typical ranges and the provided answer, 12°C is a plausible surface temperature after descent.

Option 4: -4°C. This would indicate a cooling of 10°C during descent, which is opposite to the physical behavior of a sinking parcel undergoing adiabatic compression. Such cooling would occur only if the parcel were rising or if an unlikely scenario involved an extremely strong inversions, which is not indicated here.

Rationale summary: The key concepts are moist (saturated) adiabatic lapse rates and the idea that sinking air compresses and warms. Among the options, only 12°C is consistent with the expected warm-up from 6°C at 1000 m when the parcel descends to the surface, whereas the other temperatures either imply undue cooling or unrealistic warming for a 1-km descent.

Now suppose the same parcel in the previous question was moist (saturated) instead of dry, but still had a temperature of 6°C at 1000 meters. If it sinks to the surface, it will have a temperature of:单项选择题

类似问题

Throughout the troposphere, the norm is that:

The figure above shows five environmental lapse rates (ELRs). Which ELR shows an isothermal layer (i.e., temperature remaining constant with height)?

Environmental lapse rate is the measure of the rate of temperature decrease with height in the atmosphere at a specific time and location.

If the environmental lapse rate is greater than the adiabatic lapse rate, the atmosphere is unstable.

Environmental lapse rate is the measure of the rate of temperature increase with height in the atmosphere at a specific time and location.

The lapse rate observed by a radiosonde is called the _____.

The rate at which temperature decreases with height in the atmosphere is called the ________.

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单