Atmospheric methane levels off: Temporary pause or a new steady-state?

Atmospheric methane levels off: Temporary pause or a new steady- state?

[1] The globally-averaged atmospheric methane abundance determined from an extensive network of surface air sampling sites was constant at 1751 ppb from 1999 through 2002. Assuming that the methane lifetime has been constant, this implies that during this 4-year period the global methane budget has been at steady state. We also observed a significant decrease in the difference between northern ...

Photosynthate allocations in rice plants: food production or atmospheric methane?

A tmospheric methane is recognized as one of the most important greenhouse gases. Sources of atmospheric methane are about 1/3 natural and 2/3 human-caused (1). Its concentration has roughly doubled in the past 100 years. This increase and any future continuation of it can affect Earth’s climate through global radiative forcing (increased forcing to date is between 0.5 and 0.7 W m 2) (2). Thus,...

Improved Quasi-Steady-State-Approximation Methods for Atmospheric Chemistry Integration

In the last fifteen years the quasi-steady-state-approximation (QSSA) method has been a commonly used method for integrating stiff ordinary differential equations arising from atmospheric chemistry problems. In this paper a theoretical analysis of the QSSA method is developed, stressing its strengths and its weaknesses. This theory leads to practical improvements to the QSSA method. New algorit...

Steady State Solution to Atmospheric Circulation Equations with Humidity Effect

Steady-state acid-base response at exercise levels close to maximum lactate steady state.

OBJECTIVE To study acid-base status during a constant-load treadmill test at exercise levels close to the maximum lactate steady-state. DESIGN Two tests were performed: one maximal and one steady-state at a load corresponding to the mean of the two ventilatory thresholds observed in the first test. SETTING University Sports Science Laboratory. PARTICIPANTS Twenty-three male Sports Science...