LDEO Seismology: Long-Period Noise

P46A-TA , LHE

Noise Levels at Different Periods

The table below gives the decibel 10% noise level (in db) for each month in several period bands. The 10% noise level is defined as the signal level not exceeded 10% of the time, based on hourly measurements. Each entry in the table is color coded with reference to the New Low Noise Model (NLNM, Peterson, 1993):
navy, -6 db < value-NLNM < -3 db
blue, -3 db < value-NLNM < 3 db
aqua, 3 db < value-NLNM < 6 db
lime, 6 db < value-NLNM < 9 db
yellow, 9 db < value-NLNM < 12 db
orange, 12 db < value-NLNM < 15 db
red, 15 db < value-NLNM < 20 db
fuchsia, 20 db < value-NLNM < 25 db
silver, value-NLNM < -6 db, value-NLNM > 25 db

Black indicates that there was an insufficient number of hourly measurements to calculate a noise level.

Noise levels (PSD) in decibels
Month Chan. Qual. # obs. 268s 228s 193s 164s 139s 118s 100s 85s 72s 61s 52s 44s 37s 32s 27s 23s 19s 16s 14s 12s 10s

201204 LHE AR 168 -153 -154 -153 -154 -154 -154 -154 -154 -155 -156 -156 -156 -157 -158 -159 -160 -158 -155 -152 -152 -153

201203 LHE AR 743 -151 -151 -152 -152 -152 -153 -153 -153 -154 -155 -155 -156 -157 -157 -158 -159 -157 -155 -153 -153 -151

201202 LHE AR 694 -140 -141 -142 -143 -144 -145 -146 -147 -148 -149 -151 -153 -154 -155 -156 -157 -156 -152 -150 -150 -147

201201 LHE AR 744 -137 -138 -139 -140 -140 -141 -142 -144 -145 -146 -148 -150 -151 -152 -154 -155 -155 -152 -150 -149 -147

201112 LHE AR 737 -137 -138 -139 -140 -140 -140 -142 -143 -145 -146 -147 -148 -150 -152 -153 -155 -155 -152 -149 -148 -146

201111 LHE AR 720 -138 -139 -139 -139 -140 -141 -142 -144 -144 -145 -146 -148 -149 -150 -152 -152 -152 -151 -149 -148 -147

201110 LHE AR 200 -140 -140 -140 -140 -141 -143 -144 -145 -146 -147 -149 -150 -151 -153 -155 -156 -155 -153 -152 -149 -150

Month	Chan.	Qual.	# obs.	268s	228s	193s	164s	139s	118s	100s	85s	72s	61s	52s	44s	37s	32s	27s	23s	19s	16s	14s	12s	10s
201204	LHE	AR	168	-153	-154	-153	-154	-154	-154	-154	-154	-155	-156	-156	-156	-157	-158	-159	-160	-158	-155	-152	-152	-153
201203	LHE	AR	743	-151	-151	-152	-152	-152	-153	-153	-153	-154	-155	-155	-156	-157	-157	-158	-159	-157	-155	-153	-153	-151
201202	LHE	AR	694	-140	-141	-142	-143	-144	-145	-146	-147	-148	-149	-151	-153	-154	-155	-156	-157	-156	-152	-150	-150	-147
201201	LHE	AR	744	-137	-138	-139	-140	-140	-141	-142	-144	-145	-146	-148	-150	-151	-152	-154	-155	-155	-152	-150	-149	-147
201112	LHE	AR	737	-137	-138	-139	-140	-140	-140	-142	-143	-145	-146	-147	-148	-150	-152	-153	-155	-155	-152	-149	-148	-146
201111	LHE	AR	720	-138	-139	-139	-139	-140	-141	-142	-144	-144	-145	-146	-148	-149	-150	-152	-152	-152	-151	-149	-148	-147
201110	LHE	AR	200	-140	-140	-140	-140	-141	-143	-144	-145	-146	-147	-149	-150	-151	-153	-155	-156	-155	-153	-152	-149	-150