The Influence of Natural and Anthropogenic Forcing on Water and Energy Balance and on Photosynthesis

Land surface processes are rarely studied in Detection and Attribution Model Inter-comparison Project (DAMIP) experiments on climate change. We analyzed a CMIP6 DAMIP historical experiment by using multi-linear regression (MLRM) and analysis of variance methods. We focused on energy and water budgets, including gross primary productivity (GPP). In MLRM, we estimated each forcing’s contribution and identified the role of natural forcing, which is usually ignored. Contributions of the forcing factors varied by region, and high-ranked variables such as net radiation could receive multiple influences. Greenhouse gases (GHG) accelerated energy and water cycles over the global land surface, including evapotranspiration, runoff, GPP, and water-use efficiency. Aerosol (AER) forcing displayed the opposite characteristics, and natural forcing accounted for short-term changes. A long-term analysis of total soil moisture and water budget indicated that as the AER increases, the available water on the global land increases continuously. In the recent past, an increase in net radiation (i.e., a lowered AER) reduced surface moisture and hastened surface water cycle (GHG effect). The results imply that aerosol emission and its counterbalance to GHG are essential to most land surface processes. The exception to this is GPP, which was overdominated by GHG effects.

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A Review on Land Surface Processes Modelling over Complex Terrain

Advances in Meteorology ◽

10.1155/2015/607181 ◽

2015 ◽

Vol 2015 ◽

pp. 1-17 ◽

Cited By ~ 15

Author(s):

Wei Zhao ◽

Ainong Li

Keyword(s):

Land Surface ◽

Complex Terrain ◽

Water Cycle ◽

Vertical Direction ◽

Good Alternative ◽

Surface Processes ◽

Surface Model ◽

Atmospheric Forcing ◽

Land Surface Processes ◽

Rapid Variation

Complex terrain, commonly represented by mountainous region, occupies nearly one-quarter of the Earth’s continental areas. An accurate understanding of water cycle, energy exchange, carbon cycle, and many other biogeophysical or biogeochemical processes in this area has become more and more important for climate change study. Due to the influences from complex topography and rapid variation in elevation, it is usually difficult for field measurements to capture the land-atmosphere interactions well, whereas land surface model (LSM) simulation provides a good alternative. A systematic review is introduced by pointing out the key issues for land surface processes simulation over complex terrain: (1) high spatial heterogeneity for land surface parameters in horizontal direction, (2) big variation of atmospheric forcing data in vertical direction related to elevation change, (3) scale effect on land surface parameterization in LSM, and (4) two-dimensional modelling which considers the gravity influence. Regarding these issues, it is promising for better simulation at this special region by involving higher spatial resolution atmospheric forcing data which can reflect the influences from topographic changes and making necessary improvements on model structure related to topographic factors. In addition, the incorporation of remote sensing techniques will significantly help to reduce uncertainties in model initialization, simulation, and validation.

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Supplementary material to "Multi-variable evaluation of land surface processes in forced and coupled modes reveals new error sources to the simulated water cycle in the IPSL climate model"

10.5194/hess-2020-438-supplement ◽

2020 ◽

Author(s):

Hiroki Mizuochi ◽

Agnes Ducharne ◽

Frédérique Cheruy ◽

Josefine Ghattas ◽

Amen Al-Yaari ◽

...

Keyword(s):

Land Surface ◽

Climate Model ◽

Water Cycle ◽

Surface Processes ◽

Coupled Modes ◽

Land Surface Processes ◽

Error Sources ◽

Supplementary Material

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Land surface processes and Sahel climate

Reviews of Geophysics ◽

10.1029/1999rg000014 ◽

2000 ◽

Vol 38 (1) ◽

pp. 117-140 ◽

Cited By ~ 8

Author(s):

Sharon Nicholson

Keyword(s):

Land Surface ◽

Surface Processes ◽

Land Surface Processes

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Land Surface Processes Relevant to Sub-seasonal to Seasonal (S2S) Prediction

Sub-Seasonal to Seasonal Prediction ◽

10.1016/b978-0-12-811714-9.00008-5 ◽

2019 ◽

pp. 165-181 ◽

Cited By ~ 7

Author(s):

Paul A. Dirmeyer ◽

Pierre Gentine ◽

Michael B. Ek ◽

Gianpaolo Balsamo

Keyword(s):

Land Surface ◽

Surface Processes ◽

Land Surface Processes

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Land Surface Processes in Hydrology

10.1007/978-3-642-60567-3 ◽

1997 ◽

Cited By ~ 2

Keyword(s):

Land Surface ◽

Surface Processes ◽

Land Surface Processes

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Impact of land–surface processes on the interannual variability of tropical climate in the LMD GCM

Climate Dynamics ◽

10.1007/s00382-002-0297-x ◽

2003 ◽

Vol 20 (6) ◽

pp. 613-633 ◽

Cited By ~ 4

Author(s):

K. Maynard ◽

J. Polcher

Keyword(s):

Interannual Variability ◽

Land Surface ◽

Tropical Climate ◽

Surface Processes ◽

Land Surface Processes

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The use of multi-tracer flask-measurements to understand changes in the land-surface processes.

10.5194/egusphere-egu21-15179 ◽

2021 ◽

Author(s):

Theertha Kariyathan ◽

Wouter Peters ◽

Julia Marshall ◽

Ana Bastos ◽

Markus Reichstein

Keyword(s):

Northern Hemisphere ◽

Land Surface ◽

Seasonal Cycle ◽

Growing Season ◽

Plant Productivity ◽

Surface Processes ◽

Terrestrial Biosphere ◽

Land Surface Processes ◽

Species Analysis

Carbon dioxide (CO2)&#160;is an important greenhouse gas, and it accounts for about 20% of the present-day anthropogenic greenhouse effect. Atmospheric CO2 is cycled between the terrestrial biosphere and the atmosphere through various land-surface processes and thus links the atmosphere and terrestrial biosphere through positive and negative feedback. Since multiple trace gas elements are linked by common biogeochemical processes, multi-species analysis is useful for reinforcing our understanding and can help in partitioning CO2 fluxes. For example,&#160;in the northern hemisphere, CO2 has a distinct seasonal cycle mainly regulated by plant photosynthesis and respiration and it&#160;has a distinct negative correlation with the&#160;seasonal cycle of the &#948;13C isotope of CO2,&#160;due to a stronger isotopic fractionation&#160;associated with terrestrial photosynthesis.&#160;Therefore, multi-species flask-data measurements are useful for the long-term analysis of various green-house gases. Here we try to&#160;infer the complex interaction between the atmosphere and the terrestrial biosphere by&#160;multi-species analysis using&#160;atmospheric flask measurement data from different NOAA flask measurement sites across the northern hemisphere.This study focuses on the long-term changes in the seasonal cycle of CO2 over the northern hemisphere and tries to attribute the observed changes to driving land-surface processes through a combined analysis of the &#948;13C seasonal cycle. For this we generate metrics of different parameters of the CO2&#160;and &#948;13C&#160;seasonal cycle like the seasonal cycle amplitude given by the peak-to-peak difference of the cycle (indicative of the amount of CO2 taken up by terrestrial uptake),&#160; the intensity of plant productivity inferred from the slope of the seasonal cycle during the growing season , length of growing season and the start of the growing season. We analyze the inter-relation between these metrics and how they change across latitude and over time.&#160;We hypothesize that the CO2 seasonal cycle amplitude is controlled both by the intensity of plant productivity and period of the active growing season and that the timing of the growing season can affect the intensity of plant productivity. We then quantify these relationships, including their variation over time and latitudes and describe the effects of an earlier start of the growing season on the intensity of plant productivity and the CO2&#160;uptake by plants.

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